CompletionItem of completions response always have `start = 0` and text prefix inclusion is mixed about java-debug

[testforstephen]

java-debug/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/protocol/Types.java

Lines 348 to 358 in 736dcac

	public static class CompletionItem {
	public String label;
	public String text;
	public String type;
	/**
	* A string that should be used when comparing this item with other items.
	*/
	public String sortText;
	public int start;
	public int number;

start = 0 should be a bug. We don't assign a value to start attribute of CompletionItem intentionally, and it's the Java compiler that gives it a default value 0 during json serialization. Our purpose is to always insert, I think we should remove start and number fields from our protocol data structure.