[webapp] Setup: translate fields placeholders (#3563)

src/pages/Setup.vue

@@ -23,17 +23,17 @@
                 </div>
 
                 <div class="form-floating mt-3">
-                    <input id="floatingInput" v-model="username" type="text" class="form-control" placeholder="Username" required data-cy="username-input">
+                    <input id="floatingInput" v-model="username" type="text" class="form-control" :placeholder="$t('Username')" required data-cy="username-input">
                     <label for="floatingInput">{{ $t("Username") }}</label>
                 </div>
 
                 <div class="form-floating mt-3">
-                    <input id="floatingPassword" v-model="password" type="password" class="form-control" placeholder="Password" required data-cy="password-input">
+                    <input id="floatingPassword" v-model="password" type="password" class="form-control" :placeholder="$t('Password')" required data-cy="password-input">
                     <label for="floatingPassword">{{ $t("Password") }}</label>
                 </div>
 
                 <div class="form-floating mt-3">
-                    <input id="repeat" v-model="repeatPassword" type="password" class="form-control" placeholder="Repeat Password" required data-cy="password-repeat-input">
+                    <input id="repeat" v-model="repeatPassword" type="password" class="form-control" :placeholder="$t('Repeat Password')" required data-cy="password-repeat-input">
                     <label for="repeat">{{ $t("Repeat Password") }}</label>
                 </div>