bin/runconnect.sh: 37: [[: not found

### step1
```bash
git clone git@github.com:apache/rocketmq-connect.git
cd rocketmq-connect
mvn -Prelease-connect -Dmaven.test.skip=true clean package -U
```

### step2

```bash
cd distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT
./bin/connect-standalone.sh
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 37: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 41: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 84: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 37: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 41: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 87: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 93: [: Linux: unexpected operator
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 37: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 41: [[: not found
/rocketmq-connect/distribution/target/rocketmq-connect-0.0.1-SNAPSHOT/rocketmq-connect-0.0.1-SNAPSHOT/bin/runconnect.sh: 110: [[: not found

```

Start with bin/runconnect.sh, especially the reported lines 37, 41, 84, 87, 93, 110, and inspect how it is invoked by bin/connect-standalone.sh. Rebuild with the provided Maven command, run ./bin/connect-standalone.sh in the affected shell environment, and confirm the startup no longer reports [[: not found or unexpected operator.

Written by the indexing model from the issue text.