Set static timestamps in protologtool output

When build outputs are deterministic, that helps improve the RBE cache
hit rate.

Bug: 325124724
Test: m out/soong/.intermediates/frameworks/base/libs/WindowManager/Shell/wm_shell_protolog_src/6c826b466f2421b82c3ec7d86f8481e7/gen/wm_shell_protolog.srcjar; zipinfo $!
Change-Id: I838eb379531ae5434d576828e6be43663122187b