fix(core): Limit the number of commands to get

[qwertyhjklxyz]

Description

When specify -CommandType Application, you get all git commands from $env:Path.
Use TotalCount to limit the number of commands to get.

Motivation and Context

Closes #6012

Relates to #5998

How Has This Been Tested?

Before:

$(Get-Command git -CommandType Application -ErrorAction Ignore).Source
C:\Program Files\Git\cmd\git.exe
C:\Program Files\Git\mingw64\bin\git.exe

After:

$(Get-Command git -CommandType Application -TotalCount 1 -ErrorAction Ignore).Source
C:\Program Files\Git\cmd\git.exe

Checklist:

• I have read the Contributing Guide.
• I have ensured that I am targeting the develop branch.
• I have updated the documentation accordingly.
• I have updated the tests accordingly.
• I have added an entry in the CHANGELOG.