Fix improper use of f string.

There was an f string without a substitution.

This also holds back pylint to 2.4.4. Pylint 2.5.2 was having parsing
errors.

Author: speedyleion

src/sphinx_c_autodoc/viewcode/__init__.py

@@ -296,7 +296,7 @@ def _insert_construct_anchor(
         f'<div class="viewcode-block" id="{C_DOMAIN_LINK_PREFIX}{prefix}">'
         + highlighted_source[start]
     )
-    highlighted_source[end] += f"</div>"
+    highlighted_source[end] += "</div>"
     for child in construct.get("children", []):
         _insert_construct_anchor(app, highlighted_source, child, prefix)
 

tox.ini

@@ -20,7 +20,8 @@ changedir =
     py{37}: {toxinidir}/tests
 deps =
     black
-    pylint
+    # Hold back 2.5.2 is causing problems..
+    pylint==2.4.4
     pycodestyle
     mypy
     flake8
@@ -70,4 +71,4 @@ show-source = True
 statistics = True
 max-complexity = 10
 max-line-length = 127
-ignore=E402,E501,E128,W292,W503,E203
+ignore=E402,E501,E128,W292,W503,E203