Address review comments

These were all nitpicks but hey, that's good news. :)

Author: pradyunsg

pyproject.toml

@@ -30,8 +30,8 @@ patches-dir = "tools/automation/vendoring/patches"
 [tool.vendoring.transformations]
 substitute = [
   # pkg_resource's vendored packages are directly vendored in pip.
-  { match='pkg_resources\.extern', replace='pip._vendor' },
-  { match='from \.extern', replace='from pip._vendor' },
+  { match='pkg_resources\.extern', replace="pip._vendor" },
+  { match='from \.extern', replace="from pip._vendor" },
 ]
 drop = [
   # contains unnecessary scripts

tox.ini

@@ -52,7 +52,7 @@ basepython = python3.8
 skip_install = True
 commands_pre =
 deps =
-    vendoring == 0.2.2
+    vendoring==0.2.2
     # Required, otherwise we interpret --no-binary :all: as
     # "do not build wheels", which fails for PEP 517 requirements
     pip>=19.3.1