[Fixed Position] cleanup (#2275)

* Delete unused files

* Remove fixed view plugin and style imports.

index.html

@@ -49,7 +49,6 @@
         openmct.install(openmct.plugins.ExampleImagery());
         openmct.install(openmct.plugins.UTCTimeSystem());
         openmct.install(openmct.plugins.ImportExport());
-        openmct.install(openmct.plugins.FixedView());
         openmct.install(openmct.plugins.AutoflowView({
             type: "telemetry.panel"
         }));