Added generic error class ConfigurationError

[masci]

What does this PR do?

See title

Motivation

We have a bunch of checks raising in case the config file is invalid and all of them redefine their own generic exception class, not a big deal but this way the code is more consistent

Review checklist

• PR has a meaningful title or PR has the no-changelog label attached
• Feature or bugfix has tests
• Git history is clean
• If PR impacts documentation, docs team has been notified or an issue has been opened on the documentation repo

[codecov-io]

Codecov Report

Merging #2367 into master will decrease coverage by 37.5%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           master    #2367       +/-   ##
===========================================
- Coverage   79.95%   42.44%   -37.51%     
===========================================
  Files         212       50      -162     
  Lines       14932     2980    -11952     
  Branches     1660      463     -1197     
===========================================
- Hits        11939     1265    -10674     
+ Misses       2551     1628      -923     
+ Partials      442       87      -355

[zippolyte]

💯