feat: xml format output

[Peefy]

feat: xml format output

closes kcl-lang/kcl#2023

[coveralls]

Pull Request Test Coverage Report for Build 20596145782

Details

• 149 of 205 (72.68%) changed or added relevant lines in 5 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+13.9%) to 29.426%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/format/yaml/yaml.go	18	20	90.0%
pkg/options/run.go	15	24	62.5%
pkg/format/json/json.go	14	25	56.0%
pkg/format/toml/toml.go	37	53	69.81%
pkg/format/xml/xml.go	65	83	78.31%

Files with Coverage Reduction	New Missed Lines	%
pkg/options/run.go	1	32.11%

Totals
Change from base Build 20431045180:	13.9%
Covered Lines:	241
Relevant Lines:	819

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💛 - Coveralls

[Mr-Czt]

how it works on element attribute, like Android's xml UI:

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

[Mr-Czt]

Should I refer to adding a new format like android-xml?