Remove no longer functional "implementations" command

It was RLS speciric and has been non functional since move to
rust-analyzer which has built-in open definition/open implementation

org.eclipse.corrosion/plugin.xml

@@ -31,8 +31,7 @@
         class="org.eclipse.corrosion.edit.RLSStreamConnectionProvider"
         id="org.eclipse.corrosion.rls"
         label="org.eclipse.corrosion.RLS"
-        clientImpl="org.eclipse.corrosion.edit.RLSClientImplementation"
-        serverInterface="org.eclipse.corrosion.edit.RLSServerInterface">
+        clientImpl="org.eclipse.corrosion.edit.RLSClientImplementation">
       </server>
       <contentTypeMapping
             contentType="org.eclipse.tm4e.language_pack.rust"
@@ -285,44 +284,6 @@
             name="%containerName.absolutePath"/>
     </extension>
 
-<!-- INCREMENTAL BUILD PROCESS -->
-   <extension
-         point="org.eclipse.ui.menus">
-      <menuContribution
-            allPopups="true"
-            locationURI="popup:#TextEditorContext?after=additions">
-        <command
-               commandId="org.eclipse.corrosion.commands.Implementations"
-               style="push">
-         </command>
-      </menuContribution>
-   </extension>
-   <extension
-          point="org.eclipse.ui.commands">
-      <command
-            categoryId="org.eclipse.lsp4e.category"
-            id="org.eclipse.corrosion.commands.Implementations"
-            name="%command.name.1">
-      </command>
-   </extension>
-   <extension
-         point="org.eclipse.ui.handlers">
-      <handler
-            class="org.eclipse.corrosion.extensions.Implementations"
-            commandId="org.eclipse.corrosion.commands.Implementations">
-         <enabledWhen>
-            <and>
-               <with
-                     variable="selection">
-                  <instanceof
-                        value="org.eclipse.jface.text.ITextSelection">
-                  </instanceof>
-               </with>
-            </and>
-         </enabledWhen>
-      </handler>
-   </extension>
-
 <!-- BREAKPOINTS -->
 	<extension point="org.eclipse.debug.ui.toggleBreakpointsTargetFactories">
       <toggleTargetFactory