normalize column names for Redshift

[minh5]

This fixes an error with column names when using RedShift, issue is detailed here #5308.

[codecov-io]

Codecov Report

Merging #5337 into master will decrease coverage by <.01%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master    #5337      +/-   ##
==========================================
- Coverage   61.33%   61.33%   -0.01%     
==========================================
  Files         369      369              
  Lines       23484    23486       +2     
  Branches     2713     2713              
==========================================
+ Hits        14405    14406       +1     
- Misses       9067     9068       +1     
  Partials       12       12

Impacted Files	Coverage Δ
superset/db_engine_specs.py	54.27% <50%> (-0.02%)	⬇️

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[minh5]

@mistercrunch did this make it through to the new releases? I do not believe I see them in 26.2 and 26.3?

[mistercrunch]

No it didn't. Adding a tag to pick it up on the next micro release

[mistercrunch]

Since you're a contributor I would recommend making your own build and pick whatever cherries you want on your build without depending on official releases.

[minh5]

Ah gotcha @mistercrunch, I'm pretty new to this. I have been doing this workaround but just wanted to know more about the process (and also to simply my deployment a bit). Many thanks