Meta: Move UCD/CLDR/TZDB downloaded artifacts to Build/caches

They currently reside under Build/<arch>, meaning that they would be
redownloaded for each architecture/toolchain build combo. Move them to a
location that can be re-used for all builds.

Meta/Azure/Caches.yml

@@ -3,7 +3,7 @@ parameters:
   arch: 'i686'
   toolchain: 'gcc'
   coverage: 'OFF'
-  build_directory: ''
+  download_cache_path: ''
   ccache_version: 1 # Increment this number if CI has trouble with ccache.
   serenity_ccache_path: ''
   serenity_ccache_size: '5G'
@@ -64,7 +64,7 @@ steps:
         key: '"time_zone_data" | Meta/CMake/time_zone_data.cmake | "$(timestamp)"'
         restoreKeys: |
             "time_zone_data" | Meta/CMake/time_zone_data.cmake
-        path: $(Build.SourcesDirectory)/${{ parameters.build_directory }}/TZDB
+        path: $(Build.SourcesDirectory)/${{ parameters.download_cache_path }}/TZDB
       displayName: 'TimeZoneData Cache'
 
     - task: Cache@2
@@ -72,7 +72,7 @@ steps:
         key: '"unicode_data" | Meta/CMake/unicode_data.cmake | "$(timestamp)"'
         restoreKeys: |
             "unicode_data" | Meta/CMake/unicode_data.cmake
-        path: $(Build.SourcesDirectory)/${{ parameters.build_directory }}/UCD
+        path: $(Build.SourcesDirectory)/${{ parameters.download_cache_path }}/UCD
       displayName: 'UnicodeData Cache'
 
     - task: Cache@2
@@ -80,5 +80,5 @@ steps:
         key: '"unicode_locale" | Meta/CMake/locale_data.cmake | "$(timestamp)"'
         restoreKeys: |
             "unicode_locale" | Meta/CMake/locale_data.cmake
-        path: $(Build.SourcesDirectory)/${{ parameters.build_directory }}/CLDR
+        path: $(Build.SourcesDirectory)/${{ parameters.download_cache_path }}/CLDR
       displayName: 'UnicodeLocale Cache'

Meta/Azure/Lagom.yml

@@ -39,7 +39,7 @@ jobs:
         os: '${{ parameters.os }}'
         arch: 'Lagom'
         toolchain: '$(toolchain)'
-        build_directory: 'Meta/Lagom/Build'
+        download_cache_path: 'Meta/Lagom/Build'
         serenity_ccache_path: '$(SERENITY_CCACHE_DIR)'
         with_remote_data_caches: true
         ${{ if eq(parameters.os, 'macOS') }}:

Meta/Azure/Serenity.yml

@@ -27,7 +27,7 @@ jobs:
         arch: '${{ parameters.arch }}'
         coverage: '${{ parameters.coverage }}'
         toolchain: 'clang'
-        build_directory: 'Build/${{ parameters.arch }}clang'
+        download_cache_path: 'Build/caches'
         toolchain_ccache_path: '$(LLVM_CCACHE_DIR)'
         toolchain_ccache_size: '$(LLVM_CCACHE_MAXSIZE)'
         serenity_ccache_path: '$(SERENITY_CCACHE_DIR)'