SL-821: When using BugSplat, don't try to upload Breakpad symbols.

With BugSplat, the Breakpad symbol files aren't generated; attempting to post
them to codeticket will fail the build.

build.sh

@@ -114,6 +114,8 @@ pre_build()
          if [ -n "${BUGSPLAT_DB:-}" ]
          then echo export BUGSPLAT_DB
               export BUGSPLAT_DB
+              echo RELEASE_CRASH_REPORTING=OFF
+              RELEASE_CRASH_REPORTING=OFF
          fi
     fi
     set -x