private void putEntry(int index, long key, int bufferId) {
		int offset = BASE + (index * ENTRY_SIZE);
		buffer.putLong(offset, key);
		buffer.putInt(offset + KEY_SIZE, bufferId);
	}
Store the child node entry (key and buffer ID) associated with the specified key index.
The entry at index is overwritten.  Since each entry is a fixed length, movement of
existing entries is not necessary.
@param index child key index
@param key child node key
@param bufferId child node buffer ID
Ghidra/Framework/DB/src/main/java/db/LongKeyInteriorNode.java