Fix exception thrown when pasting text into TMP inputfield with custom validator
How to reproduce:
1. Open the attached “TestUnityInputField.zip” project
2. Open the “SampleScene”
3. Enter Play Mode
4. Copy the Text “ABC” from the Input Field
5. Double click the Text to select it
6. Paste with Ctrl + V
7. Observe the Console Window
Expected result: No messages are shown and Text is pasted normally
Actual result: “ArgumentOutOfRangeException“ is thrown and only the first letter is shown in the Input Field