Disallow input file write access to jdigen.py am: 091ceb2bb2 am: e638766f63 am: 8352906c00

Original change: https://android-review.googlesource.com/c/platform/external/oj-libjdwp/+/1351023

Change-Id: I4233a5e5787b1234105e6b2b108b86a6268f62f5