Add tests for InSim connection and sending button packets

[mkapal]

Use mitm package which is also used in node-insim to intercept TCP socket connections.

• InSim connection
• Single button render
• Invalid button dimensions
• Button text too long
• Updating button text
• Updating button dimensions
• Unmounting buttons
• Global scope buttons
• Human player scope buttons
• Connection scope buttons
• Clearing and restoring all buttons using Shift + I
• Text align in buttons
• Button text colors
• Button variants
• Disabled buttons
• Initializing dialog with button text
• Button caption
• Max type in button chars
• Button is always on screen
• Flex component
• Button background colors
• Button ClickID per UCID
• Too many buttons per UCID
• Button onClick listener
• Button onType listener