build(deps): bump flask from 2.0.2 to 2.1.2 in /requirements

Bumps [flask](https://github.com/pallets/flask) from 2.0.2 to 2.1.2.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](pallets/flask@2.0.2...2.1.2)

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

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

requirements/requirements-ci.txt

@@ -248,7 +248,7 @@ flake8-tuple==0.4.1
     # via -r requirements-dev.txt
 flaky==3.7.0
     # via -r requirements-dev.txt
-flask==2.0.2
+flask==2.1.2
     # via
     #   -r requirements-dev.txt
     #   flask-cors
@@ -782,11 +782,8 @@ typing-extensions==3.10.0.2
     # via
     #   -r requirements-dev.txt
     #   aiohttp
-    #   astroid
-    #   black
     #   matrix-synapse
     #   mypy
-    #   pylint
     #   signedjson
 typing-inspect==0.4.0
     # via

requirements/requirements-dev.txt

@@ -218,7 +218,7 @@ flake8-tuple==0.4.1
     # via -r requirements-dev.in
 flaky==3.7.0
     # via -r requirements-dev.in
-flask==2.0.2
+flask==2.1.2
     # via
     #   -r requirements.txt
     #   flask-cors
@@ -665,11 +665,8 @@ typing-extensions==3.10.0.2
     # via
     #   -r requirements.txt
     #   aiohttp
-    #   astroid
-    #   black
     #   matrix-synapse
     #   mypy
-    #   pylint
     #   signedjson
 typing-inspect==0.4.0
     # via

requirements/requirements.txt

@@ -116,7 +116,7 @@ eth-utils==1.10.0
     #   web3
 filelock==3.6.0
     # via -r requirements.in
-flask==2.0.2
+flask==2.1.2
     # via
     #   -r requirements.in
     #   flask-cors