Add issue templates

[charlesbluca]

This PR adds issue templates roughly copying those used for cuDF - should hopefully make it easier to organize issues moving forward.

[codecov-commenter]

Codecov Report

Merging #247 (f932c6e) into main (3d4296b) will increase coverage by 100.00%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           main      #247        +/-   ##
===========================================
+ Coverage      0   100.00%   +100.00%     
===========================================
  Files         0        64        +64     
  Lines         0      2590      +2590     
  Branches      0       361       +361     
===========================================
+ Hits          0      2590      +2590     

Impacted Files	Coverage Δ
dask_sql/context.py	100.00% <0.00%> (ø)
dask_sql/physical/rex/__init__.py	100.00% <0.00%> (ø)
dask_sql/physical/rel/custom/create_model.py	100.00% <0.00%> (ø)
dask_sql/physical/rel/custom/analyze.py	100.00% <0.00%> (ø)
dask_sql/physical/rel/custom/predict.py	100.00% <0.00%> (ø)
dask_sql/server/responses.py	100.00% <0.00%> (ø)
dask_sql/physical/rex/core/input_ref.py	100.00% <0.00%> (ø)
dask_sql/input_utils/hive.py	100.00% <0.00%> (ø)
dask_sql/physical/rel/custom/drop_schema.py	100.00% <0.00%> (ø)
dask_sql/physical/rel/logical/join.py	100.00% <0.00%> (ø)
... and 54 more

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[ayushdg]

There's a failing gpuCI check unrelated to this PR. That can be addressed separately

[charlesbluca]

Yup - currently investigating that on #248, as I can't reproduce it locally