Bump pyyaml from 5.3b1 to 5.4

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 5.3b1 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](https://github.com/yaml/pyyaml/commits/5.4)

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

requirements.txt

@@ -1,19 +1,20 @@
-aiohttp==3.6.2
+-i https://pypi.python.org/simple/
 aiohttp-jinja2==1.2.0
+aiohttp==3.6.2
 async-timeout==3.0.1
 atomicwrites==1.3.0
-attrs==19.3.0
+attrs==21.2.0
 chardet==3.0.4
 docopt==0.6.2
 hbmqtt==0.9.5
-idna==2.8
-Jinja2==2.10.3
-MarkupSafe==1.1.1
+idna==3.2
+jinja2==2.10.3
+markupsafe==2.0.1
 multidict==4.5.2
-passlib==1.7.2
-PyYAML==5.3b1
-six==1.13.0
+passlib==1.7.4
+pyyaml==5.4
+six==1.16.0
 tinydb==3.15.2
-transitions==0.7.1
-websockets==8.1
+transitions==0.8.8
+websockets==9.1
 yarl==1.3.0