Fix schema org protocol

[protoroto]

Description

Fix schema.org procol:

• original commit taken from #152 by @svandeneertwegh
• fix tests and ci

References

Original pr: #152

Checklist

• [x] I have read the contribution guide
• [x] Code lint checked via inv lint
• [x] changes file included (see docs)
• [ ] Usage documentation added in case of new features
• [ ] Tests added

[coveralls]

coverage: 98.246%. remained the same when pulling 2fda34e53a6b7b6e465aa39e2c89d730a56bf7ca on protoroto:bugfix/152-fix-schema-org-protocol into 17e4fb97a6c864b8c0186ccbd2acd436f2bf6a30 on nephila:develop.

[codecov[bot]]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (17e4fb9) 97.58% compared to head (2fda34e) 97.58%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #161 +/- ## ======================================== Coverage 97.58% 97.58% ======================================== Files 8 8 Lines 456 456 Branches 78 78 ======================================== Hits 445 445 Misses 8 8 Partials 3 3 ``` | Flag | Coverage Δ | | |---|---|---| | unittests | `97.36% <100.00%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nephila#carryforward-flags-in-the-pull-request-comment) to find out more. | [Files Changed](https://app.codecov.io/gh/nephila/django-meta/pull/161?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nephila) | Coverage Δ | | |---|---|---| | [meta/templatetags/meta.py](https://app.codecov.io/gh/nephila/django-meta/pull/161?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nephila#diff-bWV0YS90ZW1wbGF0ZXRhZ3MvbWV0YS5weQ==) | `100.00% <100.00%> (ø)` | |

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