sq fixes

Author: theshadowco

src/main/java/com/github/_1c_syntax/bsl/languageserver/references/model/SymbolOccurrenceRepository.java

@@ -67,8 +67,10 @@ public Set<SymbolOccurrence> getAllBySymbol(Symbol symbol) {
    */
   public void deleteAll(Set<SymbolOccurrence> symbolOccurrences) {
     symbolOccurrences.forEach(symbolOccurrence ->
-      occurrencesToSymbols.get(symbolOccurrence.symbol()).remove(symbolOccurrence)
+      occurrencesToSymbols.computeIfPresent(symbolOccurrence.symbol(), (Symbol s, Set<SymbolOccurrence> set) -> {
+        set.remove(symbolOccurrence);
+        return set.isEmpty() ? null : set; // null => remove mapping
+      })
     );
   }
-
 }