Build GTK 4 binaries

Currently the GTK4 binaries are not build as part of the build, this has
several drawbacks:

1) If anything is adjusted for GTK4 part it might break without notice
2) We have no GTK4 binaries by default

This enables *compilation* of the gtk4 parts to see at laest everything
can be compiled.

.github/workflows/maven.yml

@@ -43,7 +43,7 @@ jobs:
     - name: Install Linux requirements
       run: |
         sudo apt-get update -qq 
-        sudo apt-get install -qq -y libgtk-3-dev freeglut3-dev webkit2gtk-driver
+        sudo apt-get install -qq -y libgtk-3-dev libgtk-4-dev freeglut3-dev webkit2gtk-driver
       if: ${{ matrix.config.native == 'gtk.linux.x86_64'}}
     - name: Pull large static Windows binaries
       run: |

binaries/pom.xml

@@ -135,12 +135,10 @@
 														</exec>
 													</then>
 													<else>
-														<property name="gtk_version" value="3.0" />
 														<exec dir="${build_dir}" executable="sh" failonerror="true">
-															<arg line="build.sh"/>
+															<arg line="build.sh -gtk-all"/>
 															<env key="SWT_JAVA_HOME" value="${SWT_JAVA_HOME}"/>
 															<env key="OUTPUT_DIR" value="${project.basedir}"/>
-															<env key="GTK_VERSION" value="${gtk_version}"/>
 															<env key="MODEL" value="${arch}"/>
 															<arg line="install clean"/>
 														</exec>