tools: add `.git-blame-ignore-revs` file

This would make the GitHub blame UI ignore the revisions mentioned in the .git-blame-ignore-revs file. For now, it ignores the change introduced in https://github.com/nodejs/node/commit/6afd3fcf653ed92063bafefa83661a076d241585 as asked for in https://github.com/nodejs/node/pull/42752#issuecomment-1100581445. This would make the GitHub blame UI ignore the revisions mentioned in the .git-blame-ignore-revs file. For now, it ignores the changes introduced in:

• https://github.com/nodejs/node/commit/1a37fd63c6b098524bb577e1db69bcb073fc5171
• https://github.com/nodejs/node/commit/f20a88fb866917d7dd489b88c233a5e123ff3271
• https://github.com/nodejs/node/commit/fe027da1f0aa8d63ed9a2c8298a45946bc674fff
• https://github.com/nodejs/node/commit/d0bf5ca90b2e816c37511e30225a373b8810ed0d
• https://github.com/nodejs/node/commit/dc88d19380b9b05f6bee7d61d87398f08124c861

Refs: https://github.blog/changelog/2022-03-24-ignore-commits-in-the-blame-view-beta Signed-off-by: Darshan Sen raisinten@gmail.com

cc @targos