refactor: standardize JsonStringified casing (#20101)

## Summary
- Rename safeParseRelativeDateFilterJSONStringified to
safeParseRelativeDateFilterJsonStringified
- Update the matching utility file, exports, tests, and workflow usages

Part of #19839.

## Validation
- CI passed

packages/twenty-server/src/modules/workflow/workflow-executor/workflow-actions/filter/utils/parse-and-evaluate-relative-date-filter.util.ts

@@ -24,7 +24,7 @@ import {
   getFirstDayOfTheWeekAsANumberForDateFNS,
   isDefined,
   type RelativeDateFilter,
-  safeParseRelativeDateFilterJSONStringified,
+  safeParseRelativeDateFilterJsonStringified,
   subUnitFromDateTime,
 } from 'twenty-shared/utils';
 
@@ -38,7 +38,7 @@ export const parseAndEvaluateRelativeDateFilter = ({
   relativeDateString: string;
 }): boolean => {
   const relativeDateFilterValue =
-    safeParseRelativeDateFilterJSONStringified(relativeDateString);
+    safeParseRelativeDateFilterJsonStringified(relativeDateString);
 
   if (!relativeDateFilterValue) {
     return false;