Add endpoints for QRP with unit tests

[xuxey]

Adds the following endpoints

PUT /events/:eventId/attendance/qr

Pass the string extracted from the QR code in the request body based on the DTO:

export class RegisterAttendeeQRDto {
  @IsString()
  token: string;
}

PUT /events/:eventId/attendance/email

Pass the email from the QRP manual input in the request body based on the DTO:

export class RegisterAttendeeEmailDto {
  @IsEmail()
  email: string;
}

Also added unit tests to verify various exceptions & behavior.

[github-actions[bot]]

Coverage report

St.:grey_question:	Category	Percentage	Covered / Total
🟡	Statements	66.67% (+1.19% 🔼)	430/645
🔴	Branches	19.44% (+4.06% 🔼)	14/72
🔴	Functions	29.89% (+1.65% 🔼)	26/87
🟡	Lines	64.37% (+1.46% 🔼)	374/581

Test suite run success

21 tests passing in 12 suites.

Report generated by 🧪jest coverage report action from 720a94b7bd71e3b11c9f050b68ec63a8ea16f52c