loader*: Migrate to swh.core.config.load_from_envvar

Related to swh-core#1532 (closed) Related to swh-core#1410

Test Plan

tox (failing until swh.core release >= 0.3.0)

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Migrated from D4007 (view on Phabricator)

Build has FAILED

Patch application report for D4007 (id=14133)

Rebasing onto 452fa224...

Current branch diff-target is up to date.

Changes applied before test

commit 61e6a4a1629d6b7b7ba5ffd84f9c719dbd0fab34
Author: Antoine R. Dumont (@ardumont) <ardumont@softwareheritage.org>
Date:   Tue Sep 22 13:52:09 2020 +0200

    loader*: Migrate to swh.core.config.load_from_envvar
    
    Related to [T1352](https://forge.softwareheritage.org/T1352 'view original for T1352 on Phabricator')
    Related to swh/devel/swh-core#1410

Link to build: https://jenkins.softwareheritage.org/job/DLDBASE/job/tests-on-diff/299/ See console output for more information: https://jenkins.softwareheritage.org/job/DLDBASE/job/tests-on-diff/299/console

Fix misindentation

Build has FAILED

Patch application report for D4007 (id=14135)

Rebasing onto 452fa224...

Current branch diff-target is up to date.

Changes applied before test

commit 0de33371f90772dae502dfc56f438f9daefd32df
Author: Antoine R. Dumont (@ardumont) <ardumont@softwareheritage.org>
Date:   Tue Sep 22 13:52:09 2020 +0200

    loader*: Migrate to swh.core.config.load_from_envvar
    
    This simplifies the loading mechanism, delegating the loading to that function.
    
    Related to [T1352](https://forge.softwareheritage.org/T1352 'view original for T1352 on Phabricator')
    Related to swh/devel/swh-core#1410

Link to build: https://jenkins.softwareheritage.org/job/DLDBASE/job/tests-on-diff/300/ See console output for more information: https://jenkins.softwareheritage.org/job/DLDBASE/job/tests-on-diff/300/console

Merge request was abandoned

closed