chore(ci): use latest tag for InfluxDB 2, use correct image for InfluxDB 2 nightly

[bednar]

Proposed Changes

• use influxdb:latest for stable InfluxDB 2
• use quay.io/influxdb/influxdb:nightly for nightly InfluxDB 2

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• mvn test completes successfully
• Commit messages are in semantic format
• Sign CLA (if not already signed)

[codecov-io]

Codecov Report

Merging #203 (bfb5777) into master (ca1c763) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #203   +/-   ##
=========================================
  Coverage     89.30%   89.30%           
  Complexity      447      447           
=========================================
  Files           139      139           
  Lines          5458     5458           
  Branches        215      215           
=========================================
  Hits           4874     4874           
  Misses          507      507           
  Partials         77       77           

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