use fossil instead of git for updating buckets

[goyalyashpal]

continuing from here: #5885

so, on the client's win 7 system, in extras/doublecmd i navigated to the scoop-apps directory, and the git-portable or whatever was taking at the top consuming whopping 300 MB of space.

this is whopping due to following reasons:

• as that system is old and constrained on disk space.
• for non-tech people who do not use git, this is way too much of a consumption by a needless superfluous application

so, i'd like to explore using main/fossil vcs for pulling the git buckets. it was only 30-40 MB the last time i used that.
and it says that it can work with git. but i don't know if it can work with remote-gits too...

versions

$ scoop --version | head -n2
Current Scoop version:
v0.3.1 - Released at 2022-11-15

[rashil2000]

See also #4881