Tests: Teach RunCMake to ignore Xcode DVTSDK warnings

On some Xcode versions, `xcodebuild` may warn:

    ... xcodebuild[...]  [MT] DVTSDK: Warning: SDK path collision for path ...

Teach RunCMake to drop such incidental lines before matching against
expected output.

Tests/RunCMake/RunCMake.cmake

@@ -156,7 +156,9 @@ function(run_cmake test)
 
     "|[^\n]*install_name_tool: warning: changes being made to the file will invalidate the code signature in:"
     "|[^\n]*xcodebuild[^\n]*DVTPlugInManager"
+    "|[^\n]*xcodebuild[^\n]*DVTSDK: Warning: SDK path collision for path"
     "|[^\n]*xcodebuild[^\n]*Requested but did not find extension point with identifier"
+    "|[^\n]*xcodebuild[^\n]*nil host used in call to allows.*HTTPSCertificateForHost"
     "|[^\n]*xcodebuild[^\n]*warning: file type[^\n]*is based on missing file type"
     "|[^\n]*objc[^\n]*: Class [^\n]* One of the two will be used. Which one is undefined."
     "|[^\n]*is a member of multiple groups"