fix(explore): temporal column mixin

[justinpark]

SUMMARY

In order to address the issue of the isTemporal property not being calculated from the mapping state in temporalColumnMixin, this commit migrates the property to the override object property.
This change ensures that the 3rd party controlOverrides can be properly overridden.

TESTING INSTRUCTIONS

Big number with Trendline works as before

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[lokeshwar9]

hey, Greetings of the day.

I wonder, if this has anything related to the below issue.
if we deselect few temporal columns in edit dataset and sync columns at any later point of time.
The configuration i applied for temporal columns are all gone and superset is mapping the all the time columns in dataset as temporal.
does this merge retains my configuration?

Thanks