Fixes aiopg hanging or raising psycopg2.OperationalError suddenly in gh-actions CI

[pcrespov]

Problem

Some jobs in our gh-actions CI suddenly experienced long delays or failures as

    async def cancel():
        self._waiter = create_future(self._loop)
        self._cancelling = True
        self._cancellation_waiter = self._waiter
>       self._conn.cancel()
E       psycopg2.OperationalError: asynchronous connection attempt underway

/opt/hostedtoolcache/Python/3.6.12/x64/lib/python3.6/site-packages/aiopg/connection.py:195: OperationalError

Found a report of a bug in aiopg with similar behaviour caused by problems resolving the hostname.

Noticed that the VM deployed in gh-actions before and after the problem had just been updated. Checking the /etc/hosts revealed multiple maps of 127.0.0.1 which might have been a reason why aiopg could not resolve it (again a pr in aiopg to address that problem)

What do these changes do?

Replacing localhost by 127.0.0.1 in all settings related with pg hostname

How to test

Run all tests and no more jobs hanging or tests raising OperationalError

[codecov]

Codecov Report

Merging #2138 (2d66bbc) into master (8670901) will increase coverage by 7.3%.
The diff coverage is 100.0%.

@@           Coverage Diff            @@
##           master   #2138     +/-   ##
========================================
+ Coverage    67.2%   74.6%   +7.3%     
========================================
  Files         409     419     +10     
  Lines       15811   16316    +505     
  Branches     1608    1612      +4     
========================================
+ Hits        10633   12176   +1543     
+ Misses       4763    3686   -1077     
- Partials      415     454     +39     

Flag	Coverage Δ
integrationtests	65.4% <ø> (+<0.1%)	⬆️
unittests	68.7% <100.0%> (+13.2%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...ages/service-library/src/servicelib/aiopg_utils.py	91.3% <100.0%> (ø)
.../simcore-sdk/src/simcore_sdk/node_data/__init__.py	0.0% <0.0%> (-100.0%)	⬇️
...core-sdk/src/simcore_sdk/node_data/data_manager.py	0.0% <0.0%> (-95.3%)	⬇️
...re-sdk/src/simcore_sdk/node_ports_v2/port_utils.py	78.9% <0.0%> (-15.8%)	⬇️
...es/simcore-sdk/src/simcore_sdk/node_ports/_item.py	79.5% <0.0%> (-14.8%)	⬇️
...ore-sdk/src/simcore_sdk/node_ports/_schema_item.py	87.5% <0.0%> (-12.5%)	⬇️
.../simcore-sdk/src/simcore_sdk/node_ports_v2/port.py	85.2% <0.0%> (-11.5%)	⬇️
...-sdk/src/simcore_sdk/node_ports_v2/nodeports_v2.py	89.7% <0.0%> (-10.3%)	⬇️
...mcore-sdk/src/simcore_sdk/node_ports/_data_item.py	80.9% <0.0%> (-9.6%)	⬇️
...mcore-sdk/src/simcore_sdk/node_ports/exceptions.py	68.5% <0.0%> (-9.3%)	⬇️
... and 148 more