sonar: ignore duplication warnings in test files (#4320)

Signed-off-by: Gergely Brautigam <182850+Skarlso@users.noreply.github.com>

sonar-project.properties

@@ -0,0 +1,2 @@
+# Ignore duplications in test files.
+sonar.cpd.exclusions = **/*_test.go