DBZ-759 Fix ColumnImpl.scale equality check

According to ErrorProne, checking Optional via operator == leads to
reference equality check. Probably want rather to check for contained
values.

debezium-core/src/main/java/io/debezium/relational/ColumnImpl.java

@@ -145,7 +145,7 @@ public boolean equals(Object obj) {
                     Strings.equalsIgnoreCase(this.charsetName(),that.charsetName()) &&
                     this.position() == that.position() &&
                     this.length() == that.length() &&
-                    this.scale() == that.scale() &&
+                    this.scale().equals(that.scale()) &&
                     this.isOptional() == that.isOptional() &&
                     this.isAutoIncremented() == that.isAutoIncremented() &&
                     this.isGenerated() == that.isGenerated() &&