backoff config is required for nextest (#5251)

backoff config is required

Co-authored-by: Alex Pyattaev <alex.pyattaev@anza.xyz>

nextest.toml

@@ -4,7 +4,7 @@ dir = "target/nextest"
 [profile.ci]
 failure-output = "immediate-final"
 slow-timeout = { period = "60s", terminate-after = 1 }
-retries = { count = 3 }
+retries = { backoff = "fixed", count = 3, delay = "1s" }
 
 [profile.ci.junit]
 path = "junit.xml"