Remove the deprecated set constructor from Skylark

The `set` constructor used to be deprecated, but it was still possible to use
it by providing --incompatible_disallow_set_constructor=false.

It's still allowed to have `set` in parts of the code that are not executed, this will be deprecated later. You can check if your code is compatible with this future change by using the flag --incompatible_disallow_uncalled_set_constructor (currently the default is "false").

RELNOTES[INC]: The flag --incompatible_disallow_set_constructor is no longer
available, the deprecated `set` constructor is not available anymore.

PiperOrigin-RevId: 176491641
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
index 105768f..39a7673 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
@@ -47,6 +47,7 @@
   public abstract boolean incompatibleDisallowDictPlus();
   public abstract boolean incompatibleDisallowKeywordOnlyArgs();
   public abstract boolean incompatibleDisallowToplevelIfStatement();
+  public abstract boolean incompatibleDisallowUncalledSetConstructor();
   public abstract boolean incompatibleListPlusEqualsInplace();
   public abstract boolean incompatibleLoadArgumentIsLabel();
   public abstract boolean incompatibleNewActionsApi();
@@ -68,6 +69,7 @@
       .incompatibleDisallowDictPlus(false)
       .incompatibleDisallowKeywordOnlyArgs(true)
       .incompatibleDisallowToplevelIfStatement(true)
+      .incompatibleDisallowUncalledSetConstructor(false)
       .incompatibleListPlusEqualsInplace(true)
       .incompatibleLoadArgumentIsLabel(false)
       .incompatibleNewActionsApi(false)
@@ -89,6 +91,7 @@
     public abstract Builder incompatibleDisallowDictPlus(boolean value);
     public abstract Builder incompatibleDisallowKeywordOnlyArgs(boolean value);
     public abstract Builder incompatibleDisallowToplevelIfStatement(boolean value);
+    public abstract Builder incompatibleDisallowUncalledSetConstructor(boolean value);
     public abstract Builder incompatibleListPlusEqualsInplace(boolean value);
     public abstract Builder incompatibleLoadArgumentIsLabel(boolean value);
     public abstract Builder incompatibleNewActionsApi(boolean value);