Maven Sonar Scanner Exclude a directory - sonarqube

Question

I am trying to exclude a directory of generated source code files from being analyzed by the Maven Sonar Scanner plugin.
My folder structure looks like this:
├── processors
│   └── src
│   └── main
│   └── java
│   └── org
│   └── protobuf
└── schemas
└── src
└── main
└── java
└── org
└── generated
└── models
└── ModelA.java
└── ModelB.java
I'm trying to exclude everything under schemas.
When I run the command I do the following:
mvn org.sonarsource.scanner.maven:sonar-maven-plugin:3.3.0.603:sonar
-Dsonar.projectKey=myProjectKey
-Dsonar.projectName=myProjectName
-Dsonar.login=myLoginKey
-Dsonar.password=myPassword
-Dsonar.language=java
-Dsonar.sources=.
-Dsonar.exclusions=schemas/**/*
-Dsonar.junit.reportPaths=target/surefire-reports
-Dsonar.jacoco.reportPaths=target/jacoco-ut.exec
The output says:
[INFO] Excluded sources:
[INFO] schemas/**/*
...
[INFO] 2 files indexed
[INFO] 0 files ignored because of inclusion/exclusion patterns
I'd like to exclude that entire directory, and all of it's contents. How do I get sonar scanner to do this?