Fix docs build (#200)

* Updates `sphinx` version to `4.0.2` in the docs requirements

* Adds temporary fix to `sphinxcontrib-mermaid` work properly with `sphinx >= 4`

* Locks `jinja2==2.11.2` in docs requirements

Author: thepabloaguilar

docs/conf.py

@@ -15,8 +15,20 @@
 import os
 import sys
 
+import sphinx
+
 sys.path.insert(0, os.path.abspath('..'))
 
+# TODO: Removes the whole if statement when the below PR is merged:
+# https://github.com/mgaitan/sphinxcontrib-mermaid/pull/71
+# From `sphinx>=4` the `ENOENT` constant was fully deprecated,
+# in order to make the things work with `sphinxcontrib-mermaid`
+# we need to mokey patch that constant.
+if sphinx.version_info[0] >= 4:
+    import errno  # noqa: WPS433
+    import sphinx.util.osutil  # noqa: I003, WPS301, WPS433
+    sphinx.util.osutil.ENOENT = errno.ENOENT
+
 
 # -- Project information -----------------------------------------------------
 

docs/requirements.txt

@@ -1,7 +1,7 @@
 # This file is used to setup env
 # to generate documentation.
 
-sphinx==3.5.4
+sphinx==4.0.2
 sphinx-autodoc-typehints==1.12.0
 sphinxcontrib-mermaid==0.6.3
 sphinx-typlog-theme==0.8.0
@@ -11,3 +11,7 @@ tomlkit==0.7.0
 
 # Dependencies of our project:
 typing-extensions==3.10.0.0
+
+# TODO: Remove this lock when we found and fix the route case.
+# See: https://github.com/typlog/sphinx-typlog-theme/issues/22
+jinja2==2.11.2