密码框禁止复制以及验证码最大字数限制调整

@@ -19,6 +19,7 @@
             type="password"
             size="medium"
             placeholder="请输入密码"
+            onpaste="return false"
             class="login-input"
             :maxlength="inputMaxLength"
             v-model.trim="loginForm.password"
@@ -31,6 +32,7 @@
               placeholder="请输入验证码"
               class="captcha-input"
               v-model.trim="loginForm.verificationCode"
+              :maxlength="4"
             )
               i(slot="prefix" class="icon validate-icon")
             <canvas width="93" height="36" id="captcha1"></canvas>