Bump typing-extensions from 3.7.4.2 to 3.7.4.3 in /requirements

Bumps [typing-extensions](https://github.com/python/typing) from 3.7.4.2 to 3.7.4.3.
- [Release notes](https://github.com/python/typing/releases)
- [Commits](python/typing@3.7.4.2...3.7.4.3)

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

Author: dependabot[bot]

requirements/requirements-ci.txt

@@ -180,7 +180,7 @@ traitlets==4.3.2          # via -r requirements-dev.txt, ipython
 treq==18.6.0              # via -r requirements-dev.txt, matrix-synapse
 twisted[tls]==20.3.0      # via -r requirements-dev.txt, matrix-synapse, treq
 typed-ast==1.4.0          # via -r requirements-dev.txt, black, mypy
-typing-extensions==3.7.4.2  # via -r requirements-dev.txt, matrix-synapse, mypy, signedjson
+typing-extensions==3.7.4.3  # via -r requirements-dev.txt, matrix-synapse, mypy, signedjson
 typing-inspect==0.4.0     # via -r requirements-dev.txt, marshmallow-dataclass
 unpaddedbase64==1.1.0     # via -r requirements-dev.txt, matrix-synapse, signedjson
 urllib3==1.25.3           # via -r requirements-dev.txt, requests

requirements/requirements-dev.txt

@@ -174,7 +174,7 @@ traitlets==4.3.2          # via ipython
 treq==18.6.0              # via matrix-synapse
 twisted[tls]==20.3.0      # via matrix-synapse, treq
 typed-ast==1.4.0          # via black, mypy
-typing-extensions==3.7.4.2  # via -r requirements.txt, matrix-synapse, mypy, signedjson
+typing-extensions==3.7.4.3  # via -r requirements.txt, matrix-synapse, mypy, signedjson
 typing-inspect==0.4.0     # via -r requirements.txt, marshmallow-dataclass
 unpaddedbase64==1.1.0     # via matrix-synapse, signedjson
 urllib3==1.25.3           # via -r requirements-docs.txt, -r requirements.txt, requests

requirements/requirements.txt

@@ -74,8 +74,8 @@ six==1.12.0               # via flask-cors, flask-restful, jsonschema, multiaddr
 structlog==20.1.0         # via -r requirements.in
 toml==0.10.1              # via -r requirements.in
 toolz==0.9.0              # via cytoolz
-typing-extensions==3.7.4.2  # via -r requirements.in
 typing-inspect==0.4.0     # via marshmallow-dataclass
+typing_extensions==3.7.4.3  # via -r requirements.in
 urllib3==1.25.3           # via requests
 varint==1.0.2             # via multiaddr
 web3==5.12.0              # via -r requirements.in, raiden-contracts