[FIX] shellcheck: do not check .git folder

[ap-wtioit]

Description

When testing #3266 locally i got the following error for files in the .git folder:

In ./.git/logs/refs/heads/master-fix_dmarc_dkim_spf.sh line 1:
0000000000000000000000000000000000000000 c7be7ca890f437acca09814b6aa791e30139ebfd Andreas Perhab <andreas.perhab@wt-io-it.at> 1681712871 +0200	branch: Created from HEAD
^-- SC2148 (error): Tips depend on target shell and yours is unknown. Add a shebang or a 'shell' directive.
                                                                                                                            ^----------^ SC2210 (warning): This is a file redirection. Was it supposed to be a comparison or fd operation?


In ./.git/logs/refs/heads/master-fix_dmarc_dkim_spf.sh line 2:
c7be7ca890f437acca09814b6aa791e30139ebfd 95c812346d6f2abf0cdd9155efa2b3ac65a3b169 Andreas Perhab <andreas.perhab@wt-io-it.at> 1681712898 +0200	rebase (finish): refs/heads/master-fix_dmarc_dkim_spf.sh onto 95c812346d6f2abf0cdd9155efa2b3ac65a3b169
                                                                                                                            ^----------^ SC2210 (warning): This is a file redirection. Was it supposed to be a comparison or fd operation?
                                                                                                                                                       ^-- SC1036 (error): '(' is invalid here. Did you forget to escape it?
                                                                                                                                                       ^-- SC1088 (error): Parsing stopped here. Invalid use of parentheses?


In ./.git/logs/refs/remotes/github/master-fix_dmarc_dkim_spf.sh line 1:
0000000000000000000000000000000000000000 1d6a0a3fc69a1377caef042ae8e4e9fd9663f8be Andreas Perhab <andreas.perhab@wt-io-it.at> 1681712984 +0200	update by push
^-- SC2148 (error): Tips depend on target shell and yours is unknown. Add a shebang or a 'shell' directive.
                                                                                                                            ^----------^ SC2210 (warning): This is a file redirection. Was it supposed to be a comparison or fd operation?


In ./.git/refs/heads/master-fix_dmarc_dkim_spf.sh line 1:
1d6a0a3fc69a1377caef042ae8e4e9fd9663f8be
^-- SC2148 (error): Tips depend on target shell and yours is unknown. Add a shebang or a 'shell' directive.


In ./.git/refs/remotes/github/master-fix_dmarc_dkim_spf.sh line 1:
1d6a0a3fc69a1377caef042ae8e4e9fd9663f8be
^-- SC2148 (error): Tips depend on target shell and yours is unknown. Add a shebang or a 'shell' directive.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)
• If necessary I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Info @wt-io-it