Fix "exclude" token parsing

[gibfahn]

What type of PR is this?

Bug fix

What package or component does this PR mostly affect?

rule

What does this PR do? Why is it needed?

It fixes the marshaling of GlobValue with non empty excludes.

Example

log.Printf("%s", bzl.FormatString(ExprFromValue(GlobValue{
	Patterns: []string{"a", "b"},
	Excludes: []string{"c", "d"},
})))

Before

Invalid, see Functions - Glob.

glob(
    [
        "a",
        "b",
    ],
    "excludes": [
        "c",
        "d",
    ],
)

After

glob(
    [
        "a",
        "b",
    ],
    exclude = [
        "c",
        "d",
    ],
)

Which issues(s) does this PR fix?

I have not filed an issue.

---

Commits (oldest to newest)

f596991 Fix "exclude" token parsing

3f0d09d test: Add e2e test

[blico]

Looks good. My only suggestion is I think it may also be helpful to add a more "end-to-end" test in rules/rules_test.go similar to https://github.com/bazelbuild/bazel-gazelle/blob/master/rule/rule_test.go#L32

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[gibfahn]

@googlebot I fixed it.

[gibfahn]

@blico sounds good, added.

[blico]

Looks good. Thank you!