Add codespell support (CI to check, not to fix) and make it fix a few typos (#10297)

Another token of gratitude for a super useful tool and service.

More about codespell: https://github.com/codespell-project/codespell .

I personally introduced it to dozens if not hundreds of projects already
and so far only positive feedback.

CI workflow has 'permissions' set only to 'read' so also should be safe.

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Signed-off-by: Yaroslav O. Halchenko <debian@onerussian.com>

tools/docker/lib/common

@@ -103,7 +103,7 @@ InstallMultiarchSupport() {
 # Function to create a docker builder using the buildkit docker-container
 # driver
 CreateBuilder() {
-    # just incase the env is not perfectly clean, remove any old instance of the builder
+    # just in case the env is not perfectly clean, remove any old instance of the builder
     docker buildx rm certbot_builder || true
     # create the builder instance
     #