message: Replace ToString with Into<String>
diff: @@ -193,16 +193,12 @@ impl BackendError {
  BackendError::OutOfGas {}
  }
  - pub fn unknown(msg: impl ToString) -> Self {
  - BackendError::Unknown {
  - msg: msg.to_string(),
  - }
  + pub fn unknown(msg: impl Into<String>) -> Self {
  + BackendError::Unknown { msg: msg.into() }
  }
  - pub fn user_err(msg: impl ToString) -> Self {
  - BackendError::UserErr {
  - msg: msg.to_string(),
  - }
  + pub fn user_err(msg: impl Into<String>) -> Self {
  + BackendError::UserErr { msg: msg.into() }
  }
  }
  