Remove MODULE_BUILD_FROM_SOURCE for gsi_release.mk

The gsi_release.mk should be agnostic of AOSP or Android. In case of
Android builds, modules should be prebuilt, however in the case of AOSP
they can be built from source. This option should now be configured at
the product makefile level

Also update the shipping API to 34

Bug: 278607630

Test: TARGET_PRODUCT=gsi_arm64 TARGET_BUILD_VARIANT=userdebug build/soong/soong_ui.bash --dumpvar-mode MODULE_BUILD_FROM_SOURCE
returns true
TARGET_PRODUCT=gsi_arm64 TARGET_BUILD_VARIANT=userdebug MODULE_BUILD_FROM_SOURCE=false build/soong/soong_ui.bash --dumpvar-mode MODULE_BUILD_FROM_SOURCE
returns false

Change-Id: I5937764d8df307ed7547363e6ba2742828779282