DEV: Fix all 'require-valid-alt-text' lints except in reused compoments

Three violations require parameters from the caller to generate valid alt text.

app/assets/javascripts/admin/templates/badges-index.hbs

@@ -1,6 +1,6 @@
 {{#d-section class="current-badges"}}
   <div class="badge-intro admin-intro">
-    <img src={{badgeIntroEmoji}} class="badge-intro-emoji">
+    <img src={{badgeIntroEmoji}} class="badge-intro-emoji" alt={{i18n 'admin.badges.badge_intro.emoji'}}>
     <div class="content-wrapper">
       <h1>{{i18n "admin.badges.badge_intro.title"}}</h1>
       <div class="external-resources">

app/assets/javascripts/admin/templates/customize-themes-index.hbs

@@ -1,5 +1,5 @@
 <div class="themes-intro admin-intro">
-  <img src={{womanArtistEmojiURL}}>
+  <img src={{womanArtistEmojiURL}} alt={{i18n "admin.customize.theme.themes_intro_emoji"}}>
   <div class="content-wrapper">
     <h1>{{i18n "admin.customize.theme.themes_intro"}}</h1>
     <div class="create-actions">

app/assets/javascripts/admin/templates/emojis.hbs

@@ -31,7 +31,7 @@
       <tbody>
         {{#each sortedEmojis as |e|}}
           <tr>
-            <th><img class="emoji emoji-custom" src={{e.url}} title={{e.name}}></th>
+            <th><img class="emoji emoji-custom" src={{e.url}} title={{e.name}} alt={{i18n "admin.emoji.alt"}}></th>
             <th>:{{e.name}}:</th>
             <th>{{e.group}}</th>
             <th>

app/assets/javascripts/discourse/templates/components/group-flair-inputs.hbs

@@ -35,13 +35,13 @@
 
   <div class="avatar-flair-preview">
     <div class="avatar-wrapper">
-      <img width="45" height="45" src={{demoAvatarUrl}} class="avatar actor">
+      <img width="45" height="45" src={{demoAvatarUrl}} class="avatar actor" alt="" role="presentation">
     </div>
 
     {{#if flairPreviewImage}}
       <div class="avatar-flair demo {{flairPreviewClasses}}" style={{flairPreviewStyle}}></div>
     {{else}}
-      <div class="avatar-flair demo {{flairPreviewClasses}}" style={{flairPreviewStyle}}>
+      <div class="avatar-flair demo {{flairPreviewClasses}}" style={{flairPreviewStyle}} role="presentation">
         {{d-icon flairPreviewIconUrl}}
       </div>
     {{/if}}

app/assets/javascripts/discourse/templates/email-login.hbs

@@ -1,6 +1,6 @@
 <div class="container email-login clearfix">
   <div class="pull-left col-image">
-    <img src={{lockImageUrl}} class="password-reset-img">
+    <img src={{lockImageUrl}} class="password-reset-img" alt={{i18n "email_login.emoji"}}>
   </div>
 
   <div class="pull-left col-form">

app/assets/javascripts/discourse/templates/invites/show.hbs

@@ -3,7 +3,7 @@
 
   <div class="two-col">
     <div class="col-image">
-      <img src={{inviteImageUrl}}>
+      <img src={{inviteImageUrl}} alt={{i18n 'invites.emoji'}}>
     </div>
 
     <div class="col-form">

app/assets/javascripts/discourse/templates/password-reset.hbs

@@ -1,6 +1,6 @@
 <div class="container password-reset clearfix">
   <div class="pull-left col-image">
-    <img src={{lockImageUrl}} class="password-reset-img">
+    <img src={{lockImageUrl}} class="password-reset-img" alt={{i18n "user.change_password.emoji"}}>
   </div>
 
   <div class="pull-left col-form">