Be more defensive with fetching schema version from Django migration records

[zerolab]

Fixes #706

[zerolab]

Here's the packaged version for this PR wagtail_localize-1.5.2a1.tar.gz

@urlsangel any chance you could give it a spin?

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.03% :tada:

Comparison is base (3f060bd) 93.23% compared to head (3552b7d) 93.27%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #712 +/- ## ========================================== + Coverage 93.23% 93.27% +0.03% ========================================== Files 47 47 Lines 3905 3908 +3 Branches 579 579 ========================================== + Hits 3641 3645 +4 Misses 154 154 + Partials 110 109 -1 ``` | [Files Changed](https://app.codecov.io/gh/wagtail/wagtail-localize/pull/712?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=wagtail) | Coverage Δ | | |---|---|---| | [wagtail\_localize/models.py](https://app.codecov.io/gh/wagtail/wagtail-localize/pull/712?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=wagtail#diff-d2FndGFpbF9sb2NhbGl6ZS9tb2RlbHMucHk=) | `96.23% <100.00%> (+0.16%)` | :arrow_up: |

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[urlsangel]

Here's the packaged version for this PR wagtail_localize-1.5.2a1.tar.gz

@urlsangel any chance you could give it a spin?

@zerolab Sure thing, I'll attempt to do so in the next hour or so 👍

[drcongo]

@zerolab I'm working on the same project as @urlsangel so consider it fixed for me too. Thank you!

[zerolab]

Great to hear. Will merge and get a release out tomorrow morning

[zerolab]

https://pypi.org/project/wagtail-localize/1.5.2/