Git history analyses won't work with Git worktrees

[claussni]

Bug report

PhpMetrics v2.7.4

Running phpmetrics with the --git option will not work inside separated git worktree directories. It will discover the git directory from a .git file as something like "/home/user/project/.git/worktrees/project-worktree" and fail to analyze it.

Executing system analyzes...fatal: not a git repository: /home/user/project/.git/worktrees/project-worktree

• https://git-scm.com/docs/git-worktree