async checkVerificationRequired() {
        // Check if import threshold is reached (could happen that a long import is in progress and we didn't check the threshold yet)
        await this.testImportThreshold();
        return this._isVerificationRequired() && !this._isVerified();
    }
Returns false if email verification is required to send an email. It also updates the verification check and might activate email verification.
Use this when sending emails.