[SLC] LazyAnnotationsBox: drop redundant synchronization

We can use less strict rule for produced annotations:
* Previously: the same annotations from `findAnnotation` and `annotations`
have the same identity
* Now: the same annotations from `findAnnotation` and `annotations`
are equals by 'equals'

^KT-56046

analysis/symbol-light-classes/testData/annotationsEquality/OverrideMethod.java

@@ -0,0 +1,6 @@
+public final class OverrideMethod /* one.OverrideMethod*/ extends one.AbstractClass {
+  @java.lang.Override()
+  public void foo();//  foo()
+
+  public  OverrideMethod();//  .ctor()
+}