refactor: move Maven utility to a separate package

[cuixq]

#1045

Considering that we want to support native Maven registry, we need MergeMavenParents from internal/manifest in internal/resolution/client, however internal/manifest imports internal/resolution/client for DependencyClient for dependency resolution, and this causes an import cycle.

This PR moves the Maven utility in internal/manifest to a separate package internal/utility/maven.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 65.42056% with 37 lines in your changes missing coverage. Please review.

Project coverage is 65.89%. Comparing base (dd4eef1) to head (84fd6e6).
Report is 2 commits behind head on main.

Files	Patch %	Lines
internal/utility/maven/maven.go	58.90%	21 Missing and 9 partials ⚠️
internal/resolution/manifest/maven.go	84.00%	0 Missing and 4 partials ⚠️
internal/manifest/maven.go	33.33%	0 Missing and 2 partials ⚠️
internal/remediation/override.go	83.33%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1193   +/-   ##
=======================================
  Coverage   65.89%   65.89%           
=======================================
  Files         167      168    +1     
  Lines       14072    14072           
=======================================
  Hits         9273     9273           
  Misses       4289     4289           
  Partials      510      510           

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