Bump snowballstemmer from 2.1.0 to 2.2.0 in /requirements (#18338)

Bumps [snowballstemmer](https://github.com/snowballstem/snowball) from 2.1.0 to 2.2.0.
- [Release notes](https://github.com/snowballstem/snowball/releases)
- [Changelog](https://github.com/snowballstem/snowball/blob/master/NEWS)
- [Commits](https://github.com/snowballstem/snowball/compare/v2.1.0...v2.2.0)

---
updated-dependencies:
- dependency-name: snowballstemmer
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements/docs.txt

@@ -95,9 +95,9 @@ sphinxcontrib-qthelp==1.0.3 \
 sphinx-rtd-theme==1.0.0 \
     --hash=sha256:4d35a56f4508cfee4c4fb604373ede6feae2a306731d533f409ef5c3496fdbd8 \
     --hash=sha256:eec6d497e4c2195fa0e8b2016b337532b8a699a68bcb22a512870e16925c6a5c
-snowballstemmer==2.1.0 \
-    --hash=sha256:b51b447bea85f9968c13b650126a888aabd4cb4463fca868ec596826325dedc2 \
-    --hash=sha256:e997baa4f2e9139951b6f4c631bad912dfd3c792467e2f03d7239464af90e914
+snowballstemmer==2.2.0 \
+    --hash=sha256:c8e1716e83cc398ae16824e5572ae04e0d9fc2c6b985fb0f900f5f0c96ecba1a \
+    --hash=sha256:09b16deb8547d3412ad7b590689584cd0fe25ec8db3be37788be3810cbf19cb1
 chardet==4.0.0 \
     --hash=sha256:f864054d66fd9118f2e67044ac8981a54775ec5b67aed0441892edb553d21da5 \
     --hash=sha256:0d6f53a15db4120f2b08c94f11e7d93d2c911ee118b6b30a04ec3ee8310179fa