ci: keep extension copying code

Author: vbarua

CONTRIBUTING.md

@@ -37,6 +37,14 @@ You can run the full code generation using the following command or use the indi
 pixi run codegen
 ```
 
+## Extension Copying
+
+Copy the core function extensions into substrait-python
+
+```
+pixi run copy-extensions
+```
+
 ## Antlr grammar
 
 Substrait uses antlr grammar to derive output types of extension functions. Make sure java is installed and ANTLR_JAR environment variable is set. Take a look at .devcontainer/Dockerfile for example setup.

gen_proto.sh copy_extension_yamls.shgen_proto.sh renamed to copy_extension_yamls.sh

@@ -56,10 +56,12 @@ update-substrait = [ { task = "update-submodule" }, { task = "codegen" }]
 
 update-submodule = "./update_submodule.sh"
 
-codegen = [{ task = "antlr" }, { task = "codegen-extensions" }]
+codegen = [{ task = "antlr" }, { task = "copy-extensions" }, { task = "codegen-extensions" }]
 
 check-codegen = "./check_codegen.sh"
 
+copy-extensions = "./copy_extension_yamls.sh"
+
 antlr = """
 	cd third_party/substrait/grammar \
 		&& antlr4 -o ../../../src/substrait/gen/antlr -Dlanguage=Python3 SubstraitType.g4 \