Quota: Update field trial testing config to match gcl

In the finch confi for the quota expansion experiment, I had to modify
the min version to 73, as the FLT bug is approved for beta on M73. As
a result, I had to update the experiment group names in the finch GCL
since I revised the target of the experiment. This change ensures that
the field trial testing config has the right experiment group name.


Change-Id: I181f92bb85884c15457a331b5a6af6ca354a0df7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1509109
Commit-Queue: Jarryd Goodman <jarrydg@chromium.org>
Commit-Queue: Alexei Svitkine <asvitkine@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638750}

testing/variations/fieldtrial_testing_config.json

@@ -3960,7 +3960,7 @@
             ],
             "experiments": [
                 {
-                    "name": "Enabled_Pool_Four_Fifths_Origin_ThreeQuarters",
+                    "name": "Enabled_Pool_Four_Fifths_Origin_ThreeQuarters_20190307",
                     "params": {
                         "PerHostRatio": "0.75",
                         "PoolSizeRatio": "0.8"