drop bazel 6 support for build_file_generation

Author: aignas

examples/build_file_generation/.bazelrc

@@ -5,6 +5,6 @@ build --enable_runfiles
 
 # The bzlmod version of this example is in examples/bzlmod_build_file_generation
 # Once WORKSPACE support is dropped, this example can be entirely deleted.
-build --experimental_enable_bzlmod=false
-
-common:bazel7.x --incompatible_python_disallow_native_rules
+common --noenable_bzlmod
+common --enable_workspace
+common --incompatible_python_disallow_native_rules