Add output methods for all remaining EIA 861 tables.

[zaneselvans]

In working through the tutorial notebooks, I realized we never added these methods for the interim EIA 861 tables, so I went ahead and did it. Would still love to make these kinds of accessors much more automatic with some kind of factory method or something, if you have any suggestions on the right way to do that @rousik.

[codecov]

Codecov Report

Merging #862 (7770b21) into sprint29 (1336376) will decrease coverage by 0.23%.
The diff coverage is 38.10%.

@@             Coverage Diff              @@
##           sprint29     #862      +/-   ##
============================================
- Coverage     71.71%   71.48%   -0.23%     
============================================
  Files            43       43              
  Lines          5072     5102      +30     
============================================
+ Hits           3637     3647      +10     
- Misses         1435     1455      +20     

Impacted Files	Coverage Δ
src/pudl/output/pudltabl.py	58.63% <38.10%> (-3.47%)	⬇️

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