feat(bump): support setting the initial_tag

[bukowa]

Description

When using bump and no tags are found we can modify default hardcoded 0.1.0

Motivation and Context

When using tags like package-name-v0.0.0 I would like proper initial version.

How Has This Been Tested?

Fixtures included.

Screenshots / Logs (if applicable)

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (no code change)
• Refactor (refactoring production code)
• Other

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.
• I have formatted the code with rustfmt.
• I checked the lints with clippy.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 25.00000% with 9 lines in your changes missing coverage. Please review.

Project coverage is 36.80%. Comparing base (8a9f9f4) to head (469baa6).
Report is 5 commits behind head on main.

Files	Patch %	Lines
git-cliff-core/src/release.rs	30.00%	7 Missing ⚠️
git-cliff/src/lib.rs	0.00%	2 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #701      +/-   ##
==========================================
- Coverage   36.89%   36.80%   -0.09%     
==========================================
  Files          18       18              
  Lines        1350     1359       +9     
==========================================
+ Hits          498      500       +2     
- Misses        852      859       +7     

Flag	Coverage Δ
unit-tests	36.80% <25.00%> (-0.09%)	⬇️

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[orhun]

Wouldn't it make more sense to use the --tag argument for this instead of an entirely new one? e.g.

# sets the tag to 1.0.0 if no tags are found
$ git cliff --bump --tag 1.0.0

This also aligns with the current use case:

# sets the unreleased changes to 1.0.0
$ git cliff --unreleased --tag 1.0.0

[bukowa]

Wouldn't it make more sense to use the --tag argument for this instead of an entirely new one? e.g.

Like that?

[orhun]

LGTM, can you fix the conflicts?

[orhun]

LGTM!