fish: functions/glmd: Add an alias for formatting logs in markdown

Adapted from Heftig's (Jan Alexander Steffens) note on IRC

git config --global alias.mdlog 'log --reverse --pretty=format:"- **%s**  %w(0,2,2)%+b"'

This will format commits in a way that's nice for pasting into MR descriptions,
assuming the commit body is markdown.

Usually used like below

git mdlog @{u}.. | wl-copy
git mdlog origin/main.. | wl-copy

fish/.config/fish/functions/glmd.fish

@@ -0,0 +1,4 @@
+function glmd --description 'Format commits in markdown for MR descriptions and copy to clipboard'
+    set -l remote (git symbolic-ref refs/remotes/origin/HEAD | awk -F'/' '{print $4}')
+    git log --reverse --pretty=format:"- **%s**  %w(0,2,2)%+b" origin/$remote.. | wl-copy
+end