fix: type error in invite email (#9606)

packages/server/email/teamInviteEmailCreator.tsx

@@ -3,7 +3,7 @@ import TeamInvite, {TeamInviteProps} from 'parabol-client/modules/email/componen
 import {headCSS} from 'parabol-client/modules/email/styles'
 import React from 'react'
 
-const subject = (inviterName: string) : string => `${inviterName} has invited you to Parabol`
+const subjectLine = (inviterName: string): string => `${inviterName} has invited you to Parabol`
 
 const teamInviteText = (props: TeamInviteProps) => {
   const {inviteeName, inviteeEmail, inviterName, inviterEmail, inviteLink, teamName} = props
@@ -21,12 +21,15 @@ The Parabol Product Team
 `
 }
 
-export default (props: TeamInviteProps) => ({
-  subject: subject(props.inviterName),
-  body: teamInviteText(props),
-  html: Oy.renderTemplate(<TeamInvite {...props} />, {
-    headCSS,
-    title: subject,
-    previewText: subject
-  })
-})
+export default (props: TeamInviteProps) => {
+  const subject = subjectLine(props.inviterName)
+  return {
+    subject,
+    body: teamInviteText(props),
+    html: Oy.renderTemplate(<TeamInvite {...props} />, {
+      headCSS,
+      title: subject,
+      previewText: subject
+    })
+  }
+}