3 projects that use SignAssembly, but not PublicSign

[omajid]

I found 3 locations in source-build-externals (in 6.0) that use <SignAssembly>true</SignAssembly> without <PublicSign>true</PublicSign>.

To get source-build working in an environment with RSA+SHA1 disabled, I had to do this hack to source-build:

sed -i -E 's|<SignAssembly>true</SignAssembly>|<SignAssembly>true</SignAssembly><PublicSign>true</PublicSign>|' \
  src/source-build/src/MSBuildLocator/src/MSBuildLocator/Microsoft.Build.Locator.csproj

sed -i -E 's|<SignAssembly>true</SignAssembly>|<SignAssembly>true</SignAssembly><PublicSign>true</PublicSign>|' \
  src/source-build/src/humanizer/src/Humanizer/Humanizer.csproj

sed -i -E 's|<SignAssembly>true</SignAssembly>|<SignAssembly>true</SignAssembly><PublicSign>true</PublicSign>|' \
  src/source-build/src/cssparser/Directory.Build.props