Update cmake dependency branches for swift-foundation-icu and swift-syntax

Author: jmschonfeld

CMakeLists.txt

@@ -75,7 +75,7 @@ else()
     message(STATUS "_SwiftFoundationICU_SourceDIR not provided, checking out local copy of swift-foundation-icu")
     FetchContent_Declare(SwiftFoundationICU
         GIT_REPOSITORY https://github.com/apple/swift-foundation-icu.git
-        GIT_TAG 0.0.9)
+        GIT_TAG main)
 endif()
 
 if (_SwiftCollections_SourceDIR)

Sources/FoundationMacros/CMakeLists.txt

@@ -43,7 +43,7 @@ if(NOT SwiftSyntax_FOUND)
     # If building at desk, check out and link against the SwiftSyntax repo's targets
     FetchContent_Declare(SwiftSyntax
         GIT_REPOSITORY https://github.com/swiftlang/swift-syntax.git
-        GIT_TAG 600.0.0)
+        GIT_TAG main)
     FetchContent_MakeAvailable(SwiftSyntax)
 else()
   message(STATUS "SwiftSyntax_DIR provided, using swift-syntax from ${SwiftSyntax_DIR}")