(chore) Loosen fhir2 dependency requirement

This commit changes the [fhir2 backend module](https://github.com/openmrs/openmrs-module-fhir2) dependency version requirement from a caret range (^1.2.0) to a range that allows any version greater than or equal to 1.2 (>=1.2).

src/routes.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://json.openmrs.org/routes.schema.json",
   "backendDependencies": {
-    "fhir2": "^1.2.0",
+    "fhir2": ">=1.2",
     "webservices.rest": "^2.24.0"
   },
   "extensions": [