Document DS_JAVA_VERSION for dependency scanning

doc/user/application_security/dependency_scanning/index.md

@@ -186,6 +186,7 @@ The following variables are used for configuring specific analyzers (used for a
 | `DS_PIP_VERSION`                        | `gemnasium-python` |                              | Force the install of a specific pip version (example: `"19.3"`), otherwise the pip installed in the Docker image is used. ([Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/12811) in GitLab 12.7) |
 | `DS_PIP_DEPENDENCY_PATH`                | `gemnasium-python` |                              | Path to load Python pip dependencies from. ([Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/12412) in GitLab 12.2) |
 | `DS_PYTHON_VERSION`                     | `retire.js`        |                              | Version of Python. If set to 2, dependencies are installed using Python 2.7 instead of Python 3.6. ([Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/12296) in GitLab 12.1)|
+| `DS_JAVA_VERSION`                       | `gemnasium-maven`  | `11`                         | Version of Java. Available versions: `8`, `11`, `13`, `14`. Maven and Gradle will use the Java version specified by this value. |
 | `MAVEN_CLI_OPTS`                        | `gemnasium-maven`  | `"-DskipTests --batch-mode"` | List of command line arguments that will be passed to `maven` by the analyzer. See an example for [using private repositories](../index.md#using-private-maven-repos). |
 | `GRADLE_CLI_OPTS`                       | `gemnasium-maven`  |                              | List of command line arguments that will be passed to `gradle` by the analyzer. |
 | `SBT_CLI_OPTS`                          | `gemnasium-maven`  |                              | List of command-line arguments that the analyzer will pass to `sbt`. |