Duplicate key allowed in inline table inside an array

[moorereason]

Describe the bug
Similar to #658

Given a=[{b=1,b=2}], go-toml returns the following (using gotoml-test-decoder):

{
  "a": [
    {
      "b": {
        "type": "integer",
        "value": "2"
      }
    }
  ]
}

To Reproduce
https://play.golang.org/p/DxoAkvnWJLI

toml.Unmarshal([]byte("a=[{b=1,b=2}]"), &v)

Expected behavior
I expected an error about duplicate keys within the inline table.

Versions

• go-toml: 6445159
• go version go1.17.1 linux/amd64

Additional context
Found while doing differential fuzzing against BurnstSushi.

[pelletier]

Should be fixed by f27a07d. As far as I know only inline tables and arrays are containers in values, so that should be the end of it 😅

[moorereason]

If not, the fuzzer will probably find it! 😄