"&" in user pw needs encoding on Auth

[mirandadanielson]

the only character I've tested with is &.

steps to recreate:

1. create a user with PW ending in &
2. attempt to auth with OrderCloudSDK.Auth.Login(username, "test&", clientid, scope)
3. observe request body in console
   grant_type:password scope:FullAccess client_id: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXXX username: USERNAME password: test (empty)

alternate recreation:

1. create a user with a & in the middle of the PW
2. attempt to auth with OrderCloudSDK.Auth.Login(username, "test&123", clientid, scope)
3. observe request body in console
   grant_type:password scope:FullAccess client_id: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXXX username: USERNAME password: test 123: