Backport PR #16347: FIX: catch warnings from pandas in cbook._check_1d

[tacaswell]

Merge pull request #16347 from tacaswell/fix_pandas_index_deprecation

FIX: catch warnings from pandas in cbook._check_1d
Conflicts:
lib/matplotlib/tests/test_axes.py
- new test in middle of section of tests not on v2.2.x yet, only kept
new test

PR Summary

PR Checklist

• Has Pytest style unit tests
• Code is Flake 8 compliant
• New features are documented, with examples if plot related
• Documentation is sphinx and numpydoc compliant
• Added an entry to doc/users/next_whats_new/ if major new feature (follow instructions in README.rst there)
• Documented in doc/api/api_changes.rst if API changed in a backward-incompatible way

[codecov]

Codecov Report

Merging #16361 into v2.2.x will decrease coverage by 1.54%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           v2.2.x   #16361      +/-   ##
==========================================
- Coverage   72.36%   70.81%   -1.55%     
==========================================
  Files         284      284              
  Lines       73383    72221    -1162     
  Branches    10426    10422       -4     
==========================================
- Hits        53100    51144    -1956     
- Misses      17519    18363     +844     
+ Partials     2764     2714      -50     

Impacted Files	Coverage Δ
lib/matplotlib/backends/backend_gtk3cairo.py	0.00% <0.00%> (-89.66%)	⬇️
lib/matplotlib/backends/windowing.py	0.00% <0.00%> (-88.24%)	⬇️
lib/matplotlib/backends/backend_tkagg.py	0.00% <0.00%> (-81.82%)	⬇️
lib/matplotlib/backends/_gtk3_compat.py	0.00% <0.00%> (-64.71%)	⬇️
lib/matplotlib/backends/backend_cairo.py	0.00% <0.00%> (-51.18%)	⬇️
lib/matplotlib/backends/backend_gtk3agg.py	0.00% <0.00%> (-45.17%)	⬇️
lib/matplotlib/backends/_backend_tk.py	0.00% <0.00%> (-43.31%)	⬇️
lib/matplotlib/backends/backend_gtk3.py	0.00% <0.00%> (-39.82%)	⬇️
lib/matplotlib/tests/test_backends_interactive.py	69.23% <0.00%> (-30.77%)	⬇️
lib/matplotlib/backends/tkagg.py	0.00% <0.00%> (-24.14%)	⬇️
... and 139 more

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