Secure Encryption Key

[cxbrgr]

The JWT key used to encrypt user tokens should be moved from appsettings to usersecrets.

An example on how to do that can be found at: https://dev.to/eduardstefanescu/jwt-authentication-with-symmetric-encryption-in-asp-net-core-2i53

Here should be the rough steps outlined:

enable user secrets
dotnet user-secrets init
generate a random key and set it in user settings
dotnet user-secrets set "JavaWebTokenSettings:EncryptionKey" "$(openssl rand -base64 32)"

Tasks for this issue:

1. Move key from appsettings to usersecrets
2. Update project documentation to include the key generation step