chore(core): expose utility to determine if db cache is enabled (#28262)

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## Current Behavior
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There is no function to determine if the db cache is enabled

## Expected Behavior
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There is a function to determine if the db cache is enabled.

## Related Issue(s)
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merged. -->

Fixes #

packages/nx/src/tasks-runner/cache.ts

@@ -29,11 +29,17 @@ export type CachedResult = {
 };
 export type TaskWithCachedResult = { task: Task; cachedResult: CachedResult };
 
+export function dbCacheEnabled(nxJson: NxJsonConfiguration = readNxJson()) {
+  return (
+    process.env.NX_DISABLE_DB !== 'true' &&
+    (nxJson.enableDbCache === true || process.env.NX_DB_CACHE === 'true')
+  );
+}
+
 // Do not change the order of these arguments as this function is used by nx cloud
 export function getCache(options: DefaultTasksRunnerOptions): DbCache | Cache {
   const nxJson = readNxJson();
-  return process.env.NX_DISABLE_DB !== 'true' &&
-    (nxJson.enableDbCache === true || process.env.NX_DB_CACHE === 'true')
+  return dbCacheEnabled(nxJson)
     ? new DbCache({
         // Remove this in Nx 21
         nxCloudRemoteCache: isNxCloudUsed(nxJson) ? options.remoteCache : null,