Bump gpflow from 2.1.1 to 2.1.2

Bumps [gpflow](https://github.com/GPflow/GPflow) from 2.1.1 to 2.1.2.
- [Release notes](https://github.com/GPflow/GPflow/releases)
- [Changelog](https://github.com/GPflow/GPflow/blob/develop/RELEASE.md)
- [Commits](GPflow/GPflow@v2.1.1...v2.1.2)

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

requirements.txt

@@ -1,6 +1,6 @@
 numpy==1.19.2
 Django==3.1.1
-gpflow==2.1.1
+gpflow==2.1.2
 python-dateutil==2.8.1
 networkx==2.5
 matplotlib==3.3.2

setup.py

@@ -40,7 +40,7 @@
     long_description=LONG_DESCRIPTION,
     long_description_content_type='text/markdown',
     setup_requires=["numpy==1.19.2",
-                    "gpflow==2.1.1"
+                    "gpflow==2.1.2"
                     ],
     install_requires=["python-dateutil==2.8.1",
                       "networkx==2.5",