chore(http_error): remove deprecated code

[jkklapp]

Part of #1853

[codecov]

Codecov Report

Merging #1900 (7d2db96) into master (a9ea4a9) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master     #1900   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           63        63           
  Lines         6722      6707   -15     
  Branches      1244      1242    -2     
=========================================
- Hits          6722      6707   -15     

Impacted Files	Coverage Δ
falcon/http_error.py	100.00% <ø> (ø)

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[vytas7]

Hi @jkklapp!
This looks good, we just need to get the newsfragment for #1853 started. The file should be called docs/_newsfragments/1853.breakingchange.rst, and describe what was removed.

[kgriffs]

@vytas7 I added the fragment

[vytas7]

I've taken the liberty of fixing a misspelling in a removed class's name, looks good otherwise 👍
Thanks @jkklapp & @kgriffs!

[vytas7]

It seems there is an unrelated error in the CPython 3.5.2 gate. There is an issue to remove 3.5 & 3.6, so either we do that first, or we can try to fix the gate for now.

[CaselIT]

It seems there is an unrelated error in the CPython 3.5.2 gate. There is an issue to remove 3.5 & 3.6, so either we do that first, or we can try to fix the gate for now.

Probably best to remove 3.5 first, since it does not make much sense to fix the gate to then remove it

[vytas7]

I've just removed that 3.5.2 gate. We still have the newest 3.5.x gate left that ought to be enough until we remove 3.5 & 3.6 support altogether.