api!: remove all oauth support and drop DC_LP_AUTH flags

BREAKING CHANGE: removed oauth2 module, dc_get_oauth2_url FFI function, DC_LP_AUTH flags and configured/serverflags, and the oauth2 parameter/field from SMTP/IMAP clients, JSON-RPC interfaces, and CLI tools.

also contains regenerated provider data after dropping oauth in the update script.

src/provider.rs

@@ -76,13 +76,6 @@ pub enum UsernamePattern {
     Emaillocalpart = 2,
 }
 
-/// Type of OAuth 2 authorization.
-#[derive(Debug, PartialEq, Eq)]
-pub enum Oauth2Authorizer {
-    /// Yandex.
-    Yandex,
-}
-
 /// Email server endpoint.
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Server {
@@ -136,9 +129,6 @@ pub struct Provider {
     /// Default configuration values to set when provider is configured.
     pub config_defaults: Option<&'static [ConfigDefault]>,
 
-    /// Type of OAuth 2 authorization if provider supports it.
-    pub oauth2_authorizer: Option<Oauth2Authorizer>,
-
     /// Options with good defaults.
     pub opt: ProviderOptions,
 }