Fix same hashCodes an different queries with include and exclude

[13wjdgk]

Closes #4032

There was a bug where the hashCodes of the exclude and include queries were identical.

The issue was caused by the hashCode calculation in HashMap, where the XOR operation between the hashCode of the key and the hashCode of the value (0 or 1) resulted in duplicate hashCodes.

Since Exclude and Include are differentiated by 0 and 1 and are put into the hashMap, they were vulnerable to returning duplicate hashCodes.

To resolve this, the fix involved combining the key and value of the HashMap into a single String and calculating the hashCode based on that.

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[13wjdgk]

Instead of toString(), I also considered the following solution.

	int result = nullSafeHashCodeForCriteria(criteria);
	
	public static int nullSafeHashCodeForCriteria(@Nullable Object obj) {
		if (obj == null) {
			return 0;
		} else if(obj instanceof Map<?,?>){
			int result = 0;
			for(Entry<?, ?> entry : ((Map<?, ?>)obj).entrySet()){
				if(entry.getValue() instanceof Integer){
					Integer value = (Integer)entry.getValue();
					int valueHashCode;
					if(value == 0){
						valueHashCode = FieldProjection.EXCLUDE.hashCode();
					}
					else if(value == 1){
						valueHashCode = FieldProjection.INCLUDE.hashCode();
					}else{
						valueHashCode = value.hashCode();
					}
					result += entry.getKey().hashCode() ^ valueHashCode;
				}else {
					result += entry.hashCode();
				}
			}
			return result;
		}

		return obj.hashCode();

	}

If you have a better idea, please let me know in the comments!

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