deps: Remove unused dependencies from gh notifier

[phlax]

Signed-off-by: Ryan Northey ryan@synca.io

Commit Message: deps: Remove unused dependencies from gh notifier
Additional Description:
Risk Level:
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Deprecated:]
[Optional API Considerations:]

[repokitteh-read-only]

CC @envoyproxy/dependency-shepherds: Your approval is needed for changes made to (bazel/.*repos.*\.bzl)|(bazel/dependency_imports\.bzl)|(api/bazel/.*\.bzl)|(.*/requirements\.txt)|(.*\.patch).

🐱

Caused by: #16813 was opened by phlax.

see: more, trace.

[phlax]

afaict not all of the deps in requirements.txt were used

i regenerated the file by removing everything apart from pygithub and slack-sdk and then reran pip-compile

[moderation]

I was wondering if their was a pip equivalent of something like go mod tidy that would remove unnecessary deps

[phlax]

not sure what go mod tidy does exactly but i dont know of any deps analysis tools that tell what is actually used in a set of given scripts or an env

in this case, there is only one script and it only has a couple of non-stdlib imports, so im pretty sure most of these deps are not required

[phlax]

i guess a difference between go and python is that with go you can ask "what is required to compile x binary" whereas in python its more like "what is going to be used in this env" which is more open-ended

[phlax]

/retest

[repokitteh-read-only]

Retrying Azure Pipelines:
Retried failed jobs in: envoy-presubmit

🐱

Caused by: a #16813 (comment) was created by @phlax.

see: more, trace.

[phlax]

ive updated this pr to incorporate bumping slack-sdk to v3.6

[moderation]

/lgtm deps

[alyssawilk]

nice catch, thanks