Raise error if expected attribute does not exist on a Container

[rly]

Currently, if a custom class is written for a spec, and the class does not have a field that corresponds to a group or dataset or attribute in the spec, no error or warning is thrown; the class writer would not be aware of their missing mapping. Since this missing field is almost certainly a bug, check for the missing field and throw an exception.

This has caught the missing Container fields for NWBFile/general/intracellular_ephys/filtering and TimeSeries/sync.

[codecov]

Codecov Report

Merging #196 into dev will decrease coverage by 0.15%.
The diff coverage is 37.5%.

@@            Coverage Diff             @@
##              dev     #196      +/-   ##
==========================================
- Coverage   70.42%   70.27%   -0.16%     
==========================================
  Files          30       30              
  Lines        5907     5920      +13     
  Branches     1382     1385       +3     
==========================================
  Hits         4160     4160              
- Misses       1316     1326      +10     
- Partials      431      434       +3

Impacted Files	Coverage Δ
src/hdmf/common/table.py	54.73% <36.36%> (-0.25%)	⬇️
src/hdmf/build/map.py	67.02% <40%> (-0.6%)	⬇️

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