py27 ie11 deprecation warnings

[nucleogenesis]

Summary

Implements banner for deprecation warnings in Device for py2.7 and IE11.

Follow-up Tasks

• Probably can remove py27...() function and call to sys directly. I'd moved them out of the plugin_data method's scope trying to debug why the Device plugin was failing to enable - I'm wrapping for the day so I'll update this tomorrow
  ~- [ ] Looking to write front-end tests for the banner to put a bow on this ~
• Not super sure right now on how to test the plugin_data from the backend side and it's fairly low-risk code so I'll probably skip

References

Closes #10482

Reviewer guidance

• Use IE11 on your server and view content as a sign-in user (if you've used IE11 on this database before, skip this step)

• Go to Device as super admin and see the warning re: IE11

• Run the pex using Python 2.7

• Go to Device as super admin and see the warning re: Python 2.7

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Testing checklist

• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Critical and brittle code paths are covered by unit tests

PR process

• PR has the correct target branch and milestone
• PR has 'needs review' or 'work-in-progress' label
• If PR is ready for review, a reviewer has been added. (Don't use 'Assignees')
• If this is an important user-facing change, PR or related issue has a 'changelog' label
• If this includes an internal dependency change, a link to the diff is provided

Reviewer checklist

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-0.16.0a15.dev0_git.37.g1e575576.pex
Windows Installer (EXE)	kolibri-0.16.0a15.dev0+git.37.g1e575576-unsigned.exe
Debian Package	kolibri_0.16.0a15.dev0+git.37.g1e575576-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.16.0a15.dev0+git.37.g1e575576-0.3.0.dmg
Source Tarball	kolibri-0.16.0a15.dev0+git.37.g1e575576.tar.gz
WHL file	kolibri-0.16.0a15.dev0+git.37.g1e575576-py2.py3-none-any.whl

[rtibbles]

Sorry, issue was incomplete - we need to detect two IE11 scenarios and flag accordingly.

If both conditions are true, I think the "this browser is IE11" message should take priority.

[rtibbles]

It seems this got skipped from the design, but we scoped strings to handle two scenarios:

1. The current browser you are using is IE11
2. Users of this Kolibri are using IE11

At the moment, we are only detecting (2), but the displayed message seems more like (1) is happening to the user.

I have IE11 users on my device, so I see this, in Chrome:

We should add an extra paragraph in the IE11 warning, conditionalized on whether there are detected IE11 users on the device, or whether the current browser is IE11. If the former, we should display this above the current message: https://github.com/learningequality/kolibri/blob/develop/kolibri/core/assets/src/mixins/commonCoreStrings.js#L1297 if the latter, we should display this one: https://github.com/learningequality/kolibri/blob/develop/kolibri/core/assets/src/mixins/commonCoreStrings.js#L1292

[rtibbles]

This is showing both texts in the case that both apply:

Although, I think it reads OK.