[tools][cts] Add GetRawResults test coverage

Adds test coverage for the results.GetRawResults function.

Bug: chromium:342554800, chromium:342446313
Change-Id: Ib926c539dc3a3a63e86999b1a205aaf3a588d24a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/189693
Auto-Submit: Brian Sheedy <bsheedy@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
diff --git a/go.sum b/go.sum
index 2e106ed..80595c5 100644
--- a/go.sum
+++ b/go.sum
@@ -187,6 +187,8 @@
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/texttheater/golang-levenshtein v1.0.1 h1:+cRNoVrfiwufQPhoMzB6N0Yf/Mqajr6t1lOv8GyGE2U=
 github.com/texttheater/golang-levenshtein v1.0.1/go.mod h1:PYAKrbF5sAiq9wd+H82hs7gNaen0CplQ9uvm6+enD/8=
 github.com/tidwall/jsonc v0.3.2 h1:ZTKrmejRlAJYdn0kcaFqRAKlxxFIC21pYq8vLa4p2Wc=