## Description
Updating fixtures to replace executeOnLoad with reactiveActions
Fixes [#39833](https://github.com/appsmithorg/appsmith/issues/39833)
## Automation
/ok-to-test tags=""
### 🔍 Cypress test results
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> [!CAUTION]
> If you modify the content in this section, you are likely to disrupt
the CI result for your PR.
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## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [ ] No
## Description
- Modified mock api url and refactored specs accordingly
**Flaky fixes below:**
- Listv2_BasicChildWidgetInteraction_spec.js
- QueryPane/Mongo_Spec.js
- CreateNewApp_spec.js
- Enabling S3_1_spec - upload case back
## Type of change
- Flaky test fix
## How Has This Been Tested?
- Cypress test runs
## Checklist:
### QA activity:
- [ ] Test plan has been approved by relevant developers
- [ ] Test plan has been peer reviewed by QA
- [ ] Cypress test cases have been added and approved by either SDET or
manual QA
- [ ] Organized project review call with relevant stakeholders after
Round 1/2 of QA
- [ ] Added Test Plan Approved label after reveiwing all Cypress test
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Co-authored-by: Aishwarya UR <aishwarya@appsmith.com>
