Exclude major black only commits from git blame (#2780)

* Exclude major black only commits from git blame

As more projects I've used have adopted `black` for styling, one minor
annoyance has been the impact that `black` commits that impact many
lines of code have on the usability of `git blame`. A co-worker
introduced me to the changes proposed here, which make the blame more
usable. As of spring last year, github now looks at
.git-blame-ignore-devs by default
(https://docs.github.com/en/repositories/working-with-files/using-files/viewing-a-file#ignore-commits-in-the-blame-view),
so the blame view in github will use these commits. devs who want their
local `git blame` will need the step added to the CONTRIBUTING.md file.

* Update .git-blame-ignore-revs

Co-authored-by: Matt Richards <45483497+m-richards@users.noreply.github.com>

---------

Co-authored-by: Matt Richards <45483497+m-richards@users.noreply.github.com>

.git-blame-ignore-revs

@@ -0,0 +1,8 @@
+# black-ification of code
+479b6e706293ff1a484e4e121682f3a105a53aa9
+7bc3166cfecdd120b544701cff5e37b4482cbbb5
+f4b749d148f0eb13e7e92fbbf7e2eae79de2543a
+373ac8bf731db1002e09859587c475a5f56c4e8b
+50c59d395bc539eb411f9a5c6cdf04d37510060a
+5dc982edbfc2633cd2c7a22ebd314d1b9b810a9a
+44dba4fde90e8010ea6c71c6cf51b34413440177

CONTRIBUTING.md

@@ -69,4 +69,8 @@ Style
 
   Then `black` and `flake8` will be run automatically each time you
   commit changes. You can skip these checks with `git commit
-  --no-verify`.
+  --no-verify`. You can also configure your local git clone to have
+  `git blame` ignore the commits that introduced large formatting-only
+  changes with:
+
+    $ git config blame.ignoreRevsFile .git-blame-ignore-revs