fix: Format Date/DateTime Query Parameters in exploded, non-container Parameter

[timgrohmann]

Fixes #22267

Tagging the committee as stated in the checklist: @TiFu @akehir @petejohansonxo @amakhrov @davidgamero @mkusaka @joscha

Change Description

Externalise the query parameter assignment into a separate mustache script and call it in the original place as well as while setting a exploded: true, non-container param.

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[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[wing328]

please follow step 3 in the pr checklist to fix https://github.com/OpenAPITools/openapi-generator/actions/runs/19011794828/job/54333510734?pr=22268

[timgrohmann]

Thanks for the advice @wing328, I adjusted the whitespace in the templates so the samples do not change. Also I tried correctly setting the commit author, lmk if that worked.

[MikeLamsma]

Hi @wing328, friendly reminder to check this out once again.

@timgrohmann Thanks for the work! We are also running into this in one of our apps.

[wing328]

let's give it a try

will try to add a test or 2 later