[REGRESSION]: Cannot set ChromiumSandbox launch option because of error "slowMo: expected number, got boolean"

[brutaldev]

Context:

• GOOD Playwright Version: 1.40.0
• BAD Playwright Version: 1.41.0
• Operating System: Windows
• Extra: None

Code Snippet

var playwright = await Playwright.CreateAsync();
var chromeLaunchOptions = new BrowserTypeLaunchOptions
{
  ChromiumSandbox = false,  // <-- This is the problem.
};
var chrome = await playwright.Chromium.LaunchAsync(chromeLaunchOptions);

Describe the bug

On the call to LaunchAsync when using BrowserTypeLaunchOptions that sets the ChromiumSandbox value(true or false), the following exception is thrown:

Microsoft.Playwright.PlaywrightException: slowMo: expected number, got boolean
   at Microsoft.Playwright.Transport.Connection.InnerSendMessageToServerAsync[T](ChannelOwner object, String method, Dictionary`2 dictionary, Boolean keepNulls) in /_/src/Playwright/Transport/Connection.cs:line 208
   at Microsoft.Playwright.Transport.Connection.WrapApiCallAsync[T](Func`1 action, Boolean isInternal) in /_/src/Playwright/Transport/Connection.cs:line 538
   at Microsoft.Playwright.Core.BrowserType.LaunchAsync(BrowserTypeLaunchOptions options) in /_/src/Playwright/Core/BrowserType.cs:line 56

Simply rolling back to 1.40.0 makes this code work again.

Basic console app:

[mxschmitt]

Folding into #2794 (comment)