[20.10] vendor: github.com/json-iterator/go v1.1.12 for Go 1.18 compatibility
full diff: 0ff49de124...024077e996
Fixes a nil-pointer exception on go 1.18;
```
=== FAIL: cli/context/kubernetes TestSaveLoadContexts (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0x40fcbc]
goroutine 19 [running]:
testing.tRunner.func1.2({0xa7e080, 0x1073930})
/usr/local/go/src/testing/testing.go:1389 +0x24e
testing.tRunner.func1()
/usr/local/go/src/testing/testing.go:1392 +0x39f
panic({0xa7e080, 0x1073930})
/usr/local/go/src/runtime/panic.go:838 +0x207
reflect.mapiternext(0x40?)
/usr/local/go/src/runtime/map.go:1378 +0x19
github.com/docker/cli/vendor/github.com/modern-go/reflect2.(*UnsafeMapIterator).UnsafeNext(0x8?)
/go/src/github.com/docker/cli/vendor/github.com/modern-go/reflect2/unsafe_map.go:136 +0x32
github.com/docker/cli/vendor/github.com/json-iterator/go.(*sortKeysMapEncoder).Encode(0xc000478930, 0xc0000ca3a8, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_map.go:293 +0x335
github.com/docker/cli/vendor/github.com/json-iterator/go.(*placeholderEncoder).Encode(0xc00046c898?, 0x95d787?, 0xc0000bae58?)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect.go:327 +0x22
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structFieldEncoder).Encode(0xc000482630, 0xa2790c?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:110 +0x56
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structEncoder).Encode(0xc000482780, 0xb3a599?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:158 +0x652
github.com/docker/cli/vendor/github.com/json-iterator/go.(*placeholderEncoder).Encode(0xc00046ca10?, 0x95d787?, 0xc0000bae58?)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect.go:327 +0x22
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structFieldEncoder).Encode(0xc0004829f0, 0xa0fd11?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:110 +0x56
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structEncoder).Encode(0xc000482a50, 0x40aa15?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:158 +0x652
github.com/docker/cli/vendor/github.com/json-iterator/go.(*sliceEncoder).Encode(0xc00047e198, 0xc0003a83c8, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_slice.go:38 +0x2bb
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structFieldEncoder).Encode(0xc0004837a0, 0xa12e12?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:110 +0x56
github.com/docker/cli/vendor/github.com/json-iterator/go.(*structEncoder).Encode(0xc000483890, 0x0?, 0xc0000bae40)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_struct_encoder.go:158 +0x652
github.com/docker/cli/vendor/github.com/json-iterator/go.(*OptionalEncoder).Encode(0xc0003b6be0?, 0x0?, 0x0?)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect_optional.go:74 +0xa4
github.com/docker/cli/vendor/github.com/json-iterator/go.(*onePtrEncoder).Encode(0xc000471e30, 0xc0003a8370, 0xc000460720?)
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect.go:214 +0x82
github.com/docker/cli/vendor/github.com/json-iterator/go.(*Stream).WriteVal(0xc0000bae40, {0xabe4a0, 0xc0003a8370})
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/reflect.go:93 +0x158
github.com/docker/cli/vendor/github.com/json-iterator/go.(*frozenConfig).Marshal(0xc0003b6be0, {0xabe4a0, 0xc0003a8370})
/go/src/github.com/docker/cli/vendor/github.com/json-iterator/go/config.go:299 +0xc9
github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime/serializer/json.(*Serializer).Encode(0xc00043aee0?, {0xc375c0?, 0xc0003a8370?}, {0xc339e0, 0xc000460210})
/go/src/github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go:310 +0x6d
github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime/serializer/versioning.(*codec).Encode(0xc0000f8480, {0xc37570?, 0xc0000bacc0}, {0xc339e0, 0xc000460210})
/go/src/github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime/serializer/versioning/versioning.go:231 +0x926
github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime.Encode({0x7f48b36ce5c0, 0xc0000f8480}, {0xc37570, 0xc0000bacc0})
/go/src/github.com/docker/cli/vendor/k8s.io/apimachinery/pkg/runtime/codec.go:46 +0x64
github.com/docker/cli/vendor/k8s.io/client-go/tools/clientcmd.Write(...)
/go/src/github.com/docker/cli/vendor/k8s.io/client-go/tools/clientcmd/loader.go:469
github.com/docker/cli/cli/context/kubernetes.TestSaveLoadContexts(0xc0004561a0?)
/go/src/github.com/docker/cli/cli/context/kubernetes/endpoint_test.go:75 +0xf0a
testing.tRunner(0xc0004561a0, 0xb89ea0)
/usr/local/go/src/testing/testing.go:1439 +0x102
created by testing.(*T).Run
/usr/local/go/src/testing/testing.go:1486 +0x35f
```
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>