remote-feature-flag-controller: Fix flaky test (#5730)

The test for `generateDeterministicRandomNumber` sometimes fails because
it relies on the behavior of `uuidv4`, which is non-deterministic, and
needs to be more lenient in the range of acceptable return values.

Author: mcmire

packages/remote-feature-flag-controller/src/utils/user-segmentation-utils.test.ts

@@ -130,9 +130,9 @@ describe('user-segmentation-utils', () => {
           distribution[Math.min(distributionIndex, 9)] += 1;
         });
 
-        // Each range should have roughly 10% of the values and 30% deviation
+        // Each range should have roughly 10% of the values and 40% deviation
         const expectedPerRange = samples / ranges.length;
-        const allowedDeviation = expectedPerRange * 0.3;
+        const allowedDeviation = expectedPerRange * 0.4;
 
         // Check distribution
         distribution.forEach((count) => {