Update config to use self-contained python binaries

Build from source and remove need for virtualenv to
make it self-contained.

Test: presubmit, forrest (https://android-build.googleplex.com/builds/abtd/run/L76600000954930260)
Bug: 234458076
Ignore-AOSP-First: nearby_not_in_aosp_yet
Change-Id: Ib0afb414fdeb510577345afd650fa6f0f5b3c721
(cherry picked from commit 7599806e0655e619f7e022b38d134378addd6fc1)
Merged-In: Ib0afb414fdeb510577345afd650fa6f0f5b3c721
2 files changed