[python] Refactor icons layout in community

Icons removed from SDK package (no need to have a separate class for it), ultimate icons moved out of community module.

There are only 3 icon packages in community:
* `PythonParserIcons`
* `PythonPsiApiIcons`
* `PythonIcons` (aka `intellij.python.community.impl`)

Latter two have `.json` mapper to replace old icons with new one for New UI which is included into corresponding `.xml` file.

GitOrigin-RevId: 0438ad4485b5a82a89c81ec63ae6e575d5bb52de

python/python-parser/resources/META-INF/PythonParser.xml

@@ -6,6 +6,5 @@
               hashBangs="python"
               implementationClass="com.jetbrains.python.PythonFileType"
               fieldName="INSTANCE"/>
-    <iconMapper mappingFile="PythonPsiApiIconMappings.json"/>
   </extensions>
 </idea-plugin>