Fix trigger template rendering failure when operator template_fields differ from trigger attributes

[dabla]

Fix trigger template rendering failure when operator template_fields differ from trigger attributes as reported by @kaxil in PR #55068.

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[github-actions]

Backport failed to create: v3-2-test. View the failure log Run details

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
❌	v3-2-test

You can attempt to backport this manually by running:

cherry_picker f089b5b v3-2-test

This should apply the commit to the v3-2-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

If you don't have cherry-picker installed, see the installation guide.

[github-actions]

Hi maintainer, this PR was merged without a milestone set.
We've automatically set the milestone to Airflow 3.2.1 based on: backport label targeting v3-2-test
If this milestone is not correct, please update it to the appropriate milestone.

This comment was generated by Milestone Tag Assistant.

[dabla]

@kaxil @vatsrahul1001

Seems like the PR for template rendering with start_from_trigger didn't make it into 3.2? As I have merge conflicts for this backport and TaskInstance.defer_task doesn't exist? Is it then for 3.3?