Function generateCodeVerifier

generateCodeVerifier(length): {
    method: "S256";
    value: string;
    toCodeChallenge(): string;
}
Parameters
- length: number
  Desired length of the code verifier.
  
  NOTE: According to the RFC 7636 A code verifier must be with a length >= 43 and <= 128.
Returns {
    method: "S256";
    value: string;
    toCodeChallenge(): string;
}
An object that contains the generated codeVerifier and a method toCodeChallenge to generate the code challenge from the codeVerifier following the spec of RFC 7636.
- method: "S256"
- value: string
- toCodeChallenge:function
  - toCodeChallenge(): string
  - Returns string