[Fix](function) fix wrong nullable signature of function corr (#39380)

## Proposed changes

Issue Number: close #xxx

before `corr(nullable_x, nullable_y)` will core dump. not fixed.
no need to patch in master because the refactor
#37330 already changed the
implementation context

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/Corr.java

@@ -19,8 +19,8 @@
 
 import org.apache.doris.catalog.FunctionSignature;
 import org.apache.doris.nereids.trees.expressions.Expression;
-import org.apache.doris.nereids.trees.expressions.functions.AlwaysNullable;
 import org.apache.doris.nereids.trees.expressions.functions.ExplicitlyCastableSignature;
+import org.apache.doris.nereids.trees.expressions.functions.PropagateNullable;
 import org.apache.doris.nereids.trees.expressions.shape.UnaryExpression;
 import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
 import org.apache.doris.nereids.types.BigIntType;
@@ -39,7 +39,7 @@
  * AggregateFunction 'corr'. This class is generated by GenerateFunction.
  */
 public class Corr extends AggregateFunction
-        implements UnaryExpression, ExplicitlyCastableSignature, AlwaysNullable {
+        implements UnaryExpression, ExplicitlyCastableSignature, PropagateNullable {
 
     public static final List<FunctionSignature> SIGNATURES = ImmutableList.of(
             FunctionSignature.ret(DoubleType.INSTANCE).args(TinyIntType.INSTANCE, TinyIntType.INSTANCE),

regression-test/data/nereids_function_p0/agg_function/test_corr.out

@@ -14,3 +14,24 @@
 -- !sql --
 0.8944271909999159
 
+-- !sql1 --
+0.0
+0.0
+0.0
+0.0
+0.0
+
+-- !sql2 --
+0.0
+0.0
+0.0
+0.0
+0.0
+
+-- !sql3 --
+0.0
+0.0
+0.0
+0.0
+0.0
+

regression-test/suites/nereids_function_p0/agg_function/test_corr.groovy

@@ -82,5 +82,8 @@ suite("test_corr") {
     qt_sql "select corr(x,y) from test_corr"
 
     qt_sql "select corr(cast(x as float),cast(y as float)) from test_corr"
-    sql """ DROP TABLE IF EXISTS test_corr """
+
+    qt_sql1 "select corr(non_nullable(x), non_nullable(y)) ans from test_corr group by id order by ans"
+    qt_sql2 "select corr(x, non_nullable(y)) ans from test_corr group by id order by ans"
+    qt_sql3 "select corr(non_nullable(x), y) ans from test_corr group by id order by ans"
 }