Remove errant "-q"

Author: tianon

3.0/Dockerfile

@@ -150,7 +150,7 @@ RUN set -eux; \
 # https://issues.apache.org/jira/browse/CASSANDRA-13345
 # "The stack size specified is too small, Specify at least 328k"
 {{ if env.version == "3.0" then ( -}}
-			grep -q -- '-Xss256k' "$CASSANDRA_CONF/cassandra-env.sh"; \
+			grep -- '-Xss256k' "$CASSANDRA_CONF/cassandra-env.sh"; \
 			sed -ri 's/-Xss256k/-Xss512k/g' "$CASSANDRA_CONF/cassandra-env.sh"; \
 			grep -- '-Xss512k' "$CASSANDRA_CONF/cassandra-env.sh"; \
 {{ ) elif major == 3 then ( -}}