Precompile python sources

This signifigantly improves the startup time of soong-built
python binaries. For example, running
`m apexer && time out/host/linux-x86/bin/apexer` gives
0.734s before this cl, and 0.094s after.

Fixes: 259718110
Test: Presubmits
Change-Id: Ib19e83e2c60c39a849525be117279c318de3afa7
diff --git a/tests/lib.sh b/tests/lib.sh
index 26bdc97..0973beb 100644
--- a/tests/lib.sh
+++ b/tests/lib.sh
@@ -94,6 +94,8 @@
   symlink_directory external/go-cmp
   symlink_directory external/golang-protobuf
   symlink_directory external/starlark-go
+  symlink_directory external/python
+  symlink_directory external/sqlite
 
   touch "$MOCK_TOP/Android.bp"
 }