[Windows] Removed Git internal tools from PATH

[al-cheb]

Description

Topic discussion: #1525

Related issue:

#1525

Check list

• Related issue / work item is attached
• Tests are written (if applicable)
• Documentation is updated (if applicable)
• Changes are tested and related VM images are successfully generated

[eine]

Thanks @al-cheb! I'm really grateful for seeing this moving forward. Please, see comments below, specially regarding the manipulation of the PATH.

[MSP-Greg]

OpenSSL just released 1.1.1h, and I was reminded of an issue. From a related issue discussion:

Unix tools that are resolved from System32 folder right now, will continue to work as expected since system32 is located before in PATH)

The popular MSVC OpenSSL build places OpenSSL dll's in System32. I can't test it right now, but this may cause conflicts with MSYS2/MinGW tools loading those files? I know in the past that I've renamed them in various Actions/AppVeyor scripts. If users reshuffle Path, it isn't an issue.

And, I don't recall if it was a matter of MSYS2 OpenSSL failing install and then 'CI' resolving the dll's to the System32 files. That isn't your problem, but can produce very confusing results.

[al-cheb]

@MSP-Greg , @eine, Hello.

Could you please review the first part of PR to remove git internal tools from PATH?

Changes:

• Remove git internal tools from PATH "/o:PathOption=Cmd"
• Add symlinks to shells

Shells

Name	Target
bash.exe (Default)	C:\msys64\usr\bin\bash.exe
gitbash.exe	C:\Program Files\Git\bin\bash.exe
msysbash.exe	C:\msys64\usr\bin\bash.exe
sh.exe	C:\msys64\usr\bin\sh.exe
winbash.exe	C:\windows\System32\bash.exe

• Use sfx.exe to install msys2
• Replace git internal tools to msys2 and add small notes

Notes:

Location: C:\msys64

1. MSYS2 is pre-installed on image
2. C:\msys64\mingw64\bin is added to PATH and has lower precedence than C:\Windows\System32
3. C:\msys64\usr\bin is added to PATH and has lower precedence than C:\Windows\System32
4. Default bash.exe shell is set to the C:\msys64\usr\bin\bash.exe

• Add bash.exe to PATH -> C:\msys64\usr\bin\bash.exe

[eine]

@al-cheb, as commented in #1648 (comment), I believe there should be a stronger warning about relying on msys64 being added to the PATH by default. The proposed notes are informative only. Apart from that, LGTM.

[MSP-Greg]

LGTM