Bump snowballstemmer from 2.0.0 to 2.1.0

Bumps [snowballstemmer](https://github.com/snowballstem/snowball) from 2.0.0 to 2.1.0.
- [Release notes](https://github.com/snowballstem/snowball/releases)
- [Changelog](https://github.com/snowballstem/snowball/blob/master/NEWS)
- [Commits](snowballstem/snowball@v2.0.0...v2.1.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

docs-requirements.txt

@@ -4,26 +4,49 @@
 #
 #    pip-compile ci/rtd-requirements.in
 #
-alabaster==0.7.12         # via sphinx
-babel==2.9.0              # via sphinx
-certifi==2020.12.5        # via requests
-chardet==4.0.0            # via requests
-docutils==0.16            # via sphinx
-idna==2.10                # via requests
-imagesize==1.2.0          # via sphinx
-jinja2==2.11.2            # via sphinx
-markupsafe==1.1.1         # via jinja2
-packaging==20.8           # via sphinx
-pygments==2.7.4           # via sphinx
-pyparsing==2.4.7          # via packaging
-pytz==2020.5              # via babel
-requests==2.25.1          # via sphinx
-snowballstemmer==2.0.0    # via sphinx
-sphinx==3.4.3             # via -r docs-requirements.in
-sphinxcontrib-applehelp==1.0.2  # via sphinx
-sphinxcontrib-devhelp==1.0.2  # via sphinx
-sphinxcontrib-htmlhelp==1.0.3  # via sphinx
-sphinxcontrib-jsmath==1.0.1  # via sphinx
-sphinxcontrib-qthelp==1.0.3  # via sphinx
-sphinxcontrib-serializinghtml==1.1.4  # via sphinx
-urllib3==1.26.2           # via requests
+alabaster==0.7.12
+    # via sphinx
+babel==2.9.0
+    # via sphinx
+certifi==2020.12.5
+    # via requests
+chardet==4.0.0
+    # via requests
+docutils==0.16
+    # via sphinx
+idna==2.10
+    # via requests
+imagesize==1.2.0
+    # via sphinx
+jinja2==2.11.2
+    # via sphinx
+markupsafe==1.1.1
+    # via jinja2
+packaging==20.8
+    # via sphinx
+pygments==2.7.4
+    # via sphinx
+pyparsing==2.4.7
+    # via packaging
+pytz==2020.5
+    # via babel
+requests==2.25.1
+    # via sphinx
+snowballstemmer==2.1.0
+    # via sphinx
+sphinx==3.4.3
+    # via -r docs-requirements.in
+sphinxcontrib-applehelp==1.0.2
+    # via sphinx
+sphinxcontrib-devhelp==1.0.2
+    # via sphinx
+sphinxcontrib-htmlhelp==1.0.3
+    # via sphinx
+sphinxcontrib-jsmath==1.0.1
+    # via sphinx
+sphinxcontrib-qthelp==1.0.3
+    # via sphinx
+sphinxcontrib-serializinghtml==1.1.4
+    # via sphinx
+urllib3==1.26.2
+    # via requests

test-requirements.txt

@@ -58,7 +58,7 @@ pytz==2020.5
     # via babel
 requests==2.25.1
     # via sphinx
-snowballstemmer==2.0.0
+snowballstemmer==2.1.0
     # via sphinx
 sphinx==3.4.3
     # via -r test-requirements.in