[build-presets] Don't build SwiftSyntax on incremental bots

Incremental bots don't currently check out SwiftSyntax, so building it
fails.

Author: ahoppen

utils/build-presets.ini

@@ -328,12 +328,6 @@ swiftpm
 indexstore-db
 sourcekit-lsp
 
-swiftsyntax
-swiftsyntax-verify-generated-files
-
-skstresstester
-swiftevolve
-
 # Build Playground support
 playgroundsupport
 
@@ -1025,7 +1019,6 @@ swiftpm
 xctest
 foundation
 libdispatch
-swiftsyntax
 indexstore-db
 sourcekit-lsp
 dash-dash