Move py-jinja to src folder am: fec0515194 am: 6e27281228 am: 8d6e25a8af am: 013e2db912

Original change: https://android-review.googlesource.com/c/platform/external/python/jinja/+/2215007

Change-Id: I8207c0adf7e08808ff06d93fee07c44629ef8114
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>