Add dawn_perf_tests as a data_dep of dawn_perf_tests_temp_group

This is needed so that the script to produce the isolate can correctly
detect the binary.

Bug: dawn:208
TBR: cwallez@chromium.org
Change-Id: I62fc4c40edfe9320d55a587d2176bbd9c93bb540
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/10761
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>

BUILD.gn

@@ -942,6 +942,9 @@ group("dawn_perf_tests_temp_group") {
   deps = [
     ":dawn_perf_tests",
   ]
+  data_deps = [
+    ":dawn_perf_tests",
+  ]
 }
 
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