fix(notif/ui): Use custom application title in notifications & sign-in page (#849)

server/templates/email/test-email/html.pug

@@ -54,7 +54,7 @@ div(role='article' aria-roledescription='email' aria-label='' lang='en')
               color: #a8aaaf;\
               text-decoration: none;\
               ')
-                | Overseerr
+                | #{applicationTitle}
           tr
             td(style='width: 100%' width='100%')
               table.sm-w-full(align='center' style='\
@@ -74,7 +74,7 @@ div(role='article' aria-roledescription='email' aria-label='' lang='en')
         margin-bottom: 20px;\
         color: #51545e;\
         ')
-          a(href=applicationUrl style='color: #3869d4') Open Overseerr
+          a(href=applicationUrl style='color: #3869d4') Open #{applicationTitle}
 tr
   td
     table.sm-w-full(align='center' style='\
@@ -93,4 +93,4 @@ tr
           text-align: center;\
           color: #a8aaaf;\
           ')
-            | Overseerr.
+            | #{applicationTitle}

server/templates/email/test-email/subject.pug

@@ -1 +1 @@
-= `Test Notification - Overseerr`
+= `Test Notification - ${applicationTitle}`