Remove fixed version of `org.antlr.v4.runtime` v4.9.3

After updating the project to Eclipse >=2026-03, I had to include an old version of `org.antlr.v4.runtime` v4.9.3 in the dependencies project (see https://github.com/Echtzeitsysteme/gips/commit/cf3c5e11001897467538875ee12d615b21d6ee44), because newer versions (that would be shipped with Eclipse) were incompatible with logicng.

This issue should remind me to remove and/or update the `org.antlr.v4.runtime` dependency once logicng works correctly with newer versions.

The current latest version is v4.13.2.
- Maven central: https://mvnrepository.com/artifact/org.antlr/antlr4-runtime/4.13.2

Inspect the dependencies project and the change introduced in commit cf3c5e11001897467538875ee12d615b21d6ee44. First check whether logicng now works with the Eclipse-provided org.antlr.v4.runtime version, then remove or update the fixed 4.9.3 dependency. Done means the project builds successfully without the obsolete pin.

Written by the indexing model from the issue text.