[builds] Build swift-format as part of buildbot_linux_base

We need swift-format to be installed in the toolchain in order to run SourceKit-LSP tests that invoke the swift-format executable.

rdar://121548636

Author: ahoppen

utils/build-presets.ini

@@ -865,7 +865,6 @@ foundation
 libdispatch
 indexstore-db
 sourcekit-lsp
-swiftformat
 swiftdocc
 lit-args=-v --time-tests
 
@@ -1040,6 +1039,7 @@ validation-test
 foundation
 libdispatch
 indexstore-db
+swiftformat
 sourcekit-lsp
 lit-args=-v