[SwiftCompilerSources] Temporarily enable bootstrapping on the CI

To use new C++ interop features in SwiftCompilerSources, we need a very recent Swift compiler when building with host tools. The Swift CI currently has Swift 5.5 installed, which is unfortunately too old. Let's temporarily re-enable bootstrapping.

Author: egorzhdan

utils/build-presets.ini

@@ -594,7 +594,7 @@ enable-asan
 swift-stdlib-build-type=RelWithDebInfo
 
 # Don't do bootstrapping to speed up the build
-bootstrapping=hosttools
+# TODO: use bootstrapping=hosttools
 
 
 [preset: buildbot_incremental,tools=RA,stdlib=RD,smoketest=macosx]
@@ -1403,7 +1403,7 @@ debug-swift
 no-swift-stdlib-assertions
 
 # Don't do bootstrapping to speed up the build
-bootstrapping=hosttools
+# TODO: use bootstrapping=hosttools
 
 
 [preset: buildbot_osx_package,tools=DA,stdlib=R,use_os_runtime]
@@ -2274,7 +2274,7 @@ debug-llvm
 debug-swift
 
 # Don't do bootstrapping to speed up the build
-bootstrapping=hosttools
+# TODO: use bootstrapping=hosttools
 
 
 #===------------------------------------------------------------------------===#
@@ -2295,7 +2295,7 @@ swift-stdlib-build-type=RelWithDebInfo
 swift-stdlib-enable-assertions=true
 
 # Don't do bootstrapping to speed up the build
-bootstrapping=hosttools
+# TODO: use bootstrapping=hosttools
 
 
 #===------------------------------------------------------------------------===#