Adding developer GSI keys
Bug: 254752713
Test: build and check $OUT/installed-files-vendor-ramdisk.txt that GSI
keys are included
Change-Id: Ia4041e10156eadb37799ebdc12b33fbb3de4c54d
Merged-In: Ia4041e10156eadb37799ebdc12b33fbb3de4c54d
(cherry picked from commit c42b5e2fc5e9eeb2aee93b211b8cf2985a913930)