Simplify the OAuth client_name

Every time PleromaFE is used to login it will need to do the OAuth dance and request an app key. If the client name is not stable it will pollute the server's database with entries.

This also happens on every unauthenticated page load at the moment until #1339 is resolved

changelog.d/oauth-app-name.change

@@ -0,0 +1 @@
+Simplify the OAuth client_name to 'PleromaFE'

src/services/new_api/oauth.js

@@ -10,7 +10,8 @@ export const getOrCreateApp = ({ clientId, clientSecret, instance, commit }) =>
   const url = `${instance}/api/v1/apps`
   const form = new window.FormData()
 
-  form.append('client_name', `PleromaFE_${window.___pleromafe_commit_hash}_${(new Date()).toISOString()}`)
+  form.append('client_name', 'PleromaFE')
+  form.append('website', 'https://pleroma.social')
   form.append('redirect_uris', REDIRECT_URI)
   form.append('scopes', 'read write follow push admin')