Remove compat layers for 4.3

Author: FlorentinD

build.gradle

@@ -28,13 +28,11 @@ ext {
 
     compatibilityModules = [
             'kernel-adapter': [
-                    project(':neo4j-kernel-adapter-4.3'),
                     project(':neo4j-kernel-adapter-4.4'),
                     project(':neo4j-kernel-adapter-5.1'),
             ],
             'storage-engine-adapter': [
                     project(':storage-engine-adapter-unsupported'),
-                    project(':storage-engine-adapter-4.3'),
                     project(':storage-engine-adapter-4.4'),
                     project(':storage-engine-adapter-5.1'),
             ]