[isTypeReadonly] Conditional types are always marked as readonly

[RebeccaStevens]

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

type TestType<T> = T extends number[] ? string[] : number[];

isTypeReadonly(checker, type, {})

Expected Result

isTypeReadonly should return false

Actual Result

isTypeReadonly returns true for any conditional type.

Additional Info

Conditional types aren't being tested for and are thus being treated as primitives.

typescript-eslint/packages/type-utils/src/isTypeReadonly.ts

Lines 201 to 205 in 97c0e86

	// all non-object, non-intersection types are readonly.
	// this should only be primitive types
	if (!isObjectType(type) && !isUnionOrIntersectionType(type)) {
	return Readonlyness.Readonly;
	}

Versions

package	version
@typescript-eslint/type-utils	5.9.0
@typescript-eslint/type-utils	5.9.0
TypeScript	4.5.4
node	17.1.0

Also note the error in the template in Versions: @typescript-eslint/type-utils's version is requested twice. I assume there is supposed to be only one or one is supposed to be @typescript-eslint/experimental-utils