Address inconsistently localized entries in objects.inv

[jayaddison]

Subject: Address inconsistently localized entries in objects.inv by removing translation lazy-loader proxy class

Feature or Bugfix

• Bugfix

Purpose

Numerous packages within Debian are identified as non-reproducible during parallel builds that are performed side-by-side using builds with English-language and Estonian-language locale configurations (among other environmental differences).

One recurring cause for these appears to be that the objects.inv file generated by Sphinx contains some (often only one, or a small number) localized display names for entries.

This behaviour appears to be inconsistent as documented in #9778.

Removing the lazy-loader _TranslationProxy class mechanism appears to help based on some local testing - although I'm yet to figure out why that is precisely.

Detail

• example diffoscope link for differences from a python-psutil package build (at the time-of-writing, this displays an example objects.inv localization issue) - https://tests.reproducible-builds.org/debian/dbd/unstable/amd64/python-psutil_5.9.2-1.diffoscope.html#python-psutil-doc_-.-.---_all.deb---data.tar.xz---data.tar---.-usr-share-doc-python-psutil-doc-html-objects.inv
• I've confirmed by performing a documentation build for language=et configured via sphinx/config.py (perhaps not the correct place...) that the resulting HTML documentation build does continue to be localized as expected (naive regression test)

Relates

May resolve #9778.

[jayaddison]

After more thought, I don't think that this approach is correct. The objects.inv file should be (and is) localized. Removing the translation proxy causes builds in different languages to produce the same inventory file, but I don't believe that that's what we want (because the inventory file may be published in a native language for cross-reference from other documentation sites).