internal/scan: update test names

Renames the "no vulns" test to more accurately represent what it is
testing - which is a case where there is one vulnerability that is only
required at a module level but not part of an imported package.

Change-Id: Id22c9cf99e5e4f8ea29f73d8743b2f7822ecda33
Reviewed-on: https://go-review.googlesource.com/c/vuln/+/528195
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Zvonimir Pavlinovic <zpavlinovic@google.com>
diff --git a/internal/scan/testdata/no-vulns.json b/internal/scan/testdata/module-vuln.json
similarity index 100%
rename from internal/scan/testdata/no-vulns.json
rename to internal/scan/testdata/module-vuln.json
diff --git a/internal/scan/testdata/no-vulns.txt b/internal/scan/testdata/module-vuln.txt
similarity index 100%
rename from internal/scan/testdata/no-vulns.txt
rename to internal/scan/testdata/module-vuln.txt