🔥 Remove responsibility from Board

Connect4/connect4_lib/Sources/connect4_lib/Board.swift

@@ -67,7 +67,6 @@ public struct Board : CustomStringConvertible {
 
     mutating func insertChip(from playerId: Int, atRow row: Int, atCol col: Int) -> Bool {
         guard(isWithinBounds(row, and: col)) else { return false }
-        guard((playerId == 1 || playerId == 2)) else { return false }
         guard((_grid[row][col] == nil)) else { return false }
         
         _grid[row][col] = playerId

Connect4/connect4_lib/Tests/connect4_libTests/BoardTest.swift

@@ -87,8 +87,6 @@ final class BoardTest: XCTestCase {
         expect(withGrid: [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]], playerId: 1, secretTargetRow: 2, targetCol: 0, shouldWork: true)
         // p2, ok
         expect(withGrid: [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]], playerId: 2, secretTargetRow: 2, targetCol: 0, shouldWork: true)
-        // p3, nok
-        expect(withGrid: [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]], playerId: 3, secretTargetRow: 2, targetCol: 0, shouldWork: false)
         // out of bounds left, nok
         expect(withGrid: [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]], playerId: 1, secretTargetRow: 2, targetCol: -1, shouldWork: false)
         // out of bounds right, nok