Rename version to lp_version

Author: ubaidsk

.github/workflows/CI.yml

@@ -694,7 +694,7 @@ jobs:
         shell: bash -e -l {0}
         run: |
           ./build0.sh
-          lpython_version=$(<version)
+          lpython_version=$(<lp_version)
           ci/create_source_tarball.sh $lpython_version
 
       - name: Upload Tarball to Release