Add tag name header id for keep-a-changelog template

[wadackel]

What does this do / why do we need it?

ID was added to the title of each tag.

How this PR fixes the problem?

• None

What should your reviewer look out for in this PR?

• None

Check lists

• Test passed
• Coding style (indentation, etc)

Additional Comments (if any)

• None

Which issue(s) does this PR fix?

• None

[coveralls]

Pull Request Test Coverage Report for Build 83

• 8 of 9 (88.89%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.06%) to 72.203%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
cmd/git-chglog/custom_template_builder.go	1	2	50.0%

Totals
Change from base Build 80:	0.06%
Covered Lines:	1439
Relevant Lines:	1993

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💛 - Coveralls