Do not download from external sources (#3211)
Do not download from external sources (#3211)

This commit removes the external dependencies of the AppImage generation script by instead
downloading them from a known (and owned by Microsoft) location:
psgithub.file.core.windows.net.
TravisEz13/PowerShell,TravisEz13/PowerShell,JamesWTruher/PowerShell-1,JamesWTruher/PowerShell-1,JamesWTruher/PowerShell-1,PaulHigin/PowerShell,PaulHigin/PowerShell,PaulHigin/PowerShell,TravisEz13/PowerShell,daxian-dbw/PowerShell,PaulHigin/PowerShell,JamesWTruher/PowerShell-1,daxian-dbw/PowerShell,daxian-dbw/PowerShell,daxian-dbw/PowerShell,TravisEz13/PowerShell