Update Incognito Dynamic Quota field trial test.

Param names are updated in the field trial test.

Bug: 1017120
Change-Id: I6f3fee3faaac5f9061c097858c5b02b05c3e8fb7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1989066
Auto-Submit: Ramin Halavati <rhalavati@chromium.org>
Reviewed-by: Nik Bhagat <nikunjb@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#731744}

testing/variations/fieldtrial_testing_config.json

@@ -3177,8 +3177,8 @@
                 {
                     "name": "WideRange",
                     "params": {
-                        "RatioLowerBound": "0.1",
-                        "RatioUpperBound": "0.2"
+                        "IncognitoQuotaRatioLowerBound": "0.1",
+                        "IncognitoQuotaRatioUpperBound": "0.2"
                     },
                     "enable_features": [
                         "IncognitoDynamicQuota"