reference_contributor.md: Use PsiPolyVariantReferenceBase #1198

Job	Run time
Gradle Wrappers	5s
Code Samples / action_basics	3m 23s
Code Samples / comparing_string_references_inspection	3m 28s
Code Samples / conditional_operator_intention	3m 25s
Code Samples / editor_basics	3m 31s
Code Samples / facet_basics	3m 33s
Code Samples / framework_basics	3m 33s
Code Samples / live_templates	3m 7s
Code Samples / max_opened_projects	3m 34s
Code Samples / module	3m 9s
Code Samples / project_model	3m 10s
Code Samples / project_view_pane	3m 31s
Code Samples / project_wizard	3m 31s
Code Samples / psi_demo	3m 24s
Code Samples / run_configuration	3m 22s
Code Samples / simple_language_plugin	3m 41s
Code Samples / tool_window	3m 19s
Code Samples / tree_structure_provider	3m 30s
Code Samples Mirror	35s
	58m 51s

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