Revert "Append APEX version instead of build ID for APK-in-APEX ..."

Revert "Make apexer replace instances of version placeholder str..."

Revert submission 17944887-apk-in-apex

Reason for revert: Caused a regression (b/230873680)
Reverted Changes:
Ic37eeba8b:Make apexer replace instances of version placehold...
I9cef1418c:Append APEX version instead of build ID for APK-in...

Change-Id: I3da8bcb782baf71cddce9e4e92fe3894fc187b5c