fix(chart): chart datasource explore URL showing datasource name for druid

[dpgaspar]

SUMMARY

Bug introduced on #9619, URL for druid datasources rendering name instead of explore_url

TEST PLAN

• Create a druid cluster and datasource
• Create a chart for the previous create druid datasource
• Assert that the rendered URL for the datasource on the charts list links to the druid datasource

ADDITIONAL INFORMATION

• Has associated issue:
• Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

[codecov-commenter]

Codecov Report

Merging #9839 into master will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master    #9839   +/-   ##
=======================================
  Coverage   71.02%   71.02%           
=======================================
  Files         583      583           
  Lines       30615    30615           
  Branches     3162     3162           
=======================================
  Hits        21745    21745           
  Misses       8759     8759           
  Partials      111      111           

Flag	Coverage Δ
#cypress	53.54% <ø> (-0.01%)	⬇️
#javascript	59.29% <ø> (ø)
#python	71.27% <0.00%> (ø)

Impacted Files	Coverage Δ
superset/models/slice.py	83.78% <0.00%> (ø)

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