private String getKeepName(DomainFolder parent, String name) {
		int oneUp = 1;
		String keepName = name + ".keep";
		while (true) {
			DomainFile df = parent.getFile(keepName);
			if (df != null) {
				keepName = name + ".keep" + oneUp;
				++oneUp;
			}
			return keepName;
		}
	}
Determines a unique keep file name for saving a copy of the hijack file 
when its hijack is undone.
@param parent the domain folder where the hijacked file exists.
@param name the name of the hijacked file.
@return the unique keep file name.
Ghidra/Framework/Project/src/main/java/ghidra/framework/main/projectdata/actions/VersionControlUndoHijackAction.java