Fix code to work with 2023.1 and latest Rust plugin

Author: AzureMarker

src/main/kotlin/com/mdrobnak/lalrpop/inspections/CannotInferNonterminalTypeInspection.kt

@@ -27,17 +27,16 @@ object CannotInferNonterminalTypeInspection : LocalInspectionTool() {
                     LpMacroArguments.identity(nonterminal.nonterminalName.nonterminalParams)
                 )
 
-                val quickFix = when (type) {
+                if (type == "_") {
                     // IntelliJ-Rust was unable to resolve the type, so don't
                     // suggest the quick fix.
-                    "_" -> null
-                    else -> InferFromRustPluginQuickFix(type)
+                    return
                 }
 
                 holder.registerProblem(
                     nonterminal,
                     "Cannot infer type of nonterminal",
-                    quickFix,
+                    InferFromRustPluginQuickFix(type),
                 )
             }
         }

src/main/kotlin/com/mdrobnak/lalrpop/psi/ext/LpActionType.kt

@@ -41,7 +41,7 @@ fun LpActionType.nonterminalTypeFromReturn(ty: Ty): Ty = when (childrenWithLeave
     LpElementTypes.USER_ACTION, LpElementTypes.LOOKAHEAD_ACTION, LpElementTypes.LOOKBEHIND_ACTION -> ty
     LpElementTypes.FALLIBLE_ACTION ->
         ty.takeIf { (it as? TyAdt)?.item?.qualifiedName == "core::result::Result" }
-            ?.typeParameterValues?.typeByName("T")
+            ?.typeParameterValues?.typeParameterByName("T")
             ?: error("Inferred type from fallible action code(${ty.render()}) is not Result")
     else -> throw IllegalStateException("Child other than =>, =>@L, =>@R, or =>? in an action_type rule")
 }