Update pwa.html

[blackelbow]

Include crossorigin to prevent 401 when pwa is behind sign in

[Archmonger]

Hey @silviolleite , I'd like to see this PR reviewed & merged. Without this, django-pwa is not usable in any reverse proxy or auth scenario.

Code changes are only one line.

[silviolleite]

Hey @silviolleite , I'd like to see this PR reviewed & merged. Without this, django-pwa is not usable in any reverse proxy or auth scenario.

Code changes are only one line.

Thx @Archmonger
Please, you need to fix the unit tests.

[Archmonger]

@silviolleite I am not the author for this PR, and the original author appears to be inactive on GH.

The fix for the unit test is quite simple.
Line 25 of test_template_tags.py needs to be changed.
Previously was: '<link rel="manifest" href="/manifest.json">',
Needs to be '<link rel="manifest" href="/manifest.json" crossorigin="use-credentials">',

Tests will pass after this change.