Increase cache time for upgrades

Fixes #1525

app/models/provider/github.rb

@@ -8,7 +8,7 @@ class Provider::Github
   end
 
   def fetch_latest_upgrade_candidates
-    Rails.cache.fetch("latest_github_upgrade_candidates", expires_in: 2.minutes) do
+    Rails.cache.fetch("latest_github_upgrade_candidates", expires_in: 30.minutes) do
       Rails.logger.info "Fetching latest GitHub upgrade candidates from #{repo} on branch #{branch}..."
       begin
         latest_release = Octokit.releases(repo).first

config/initializers/good_job.rb

@@ -4,7 +4,7 @@ Rails.application.configure do
   if ENV["UPGRADES_ENABLED"] == "true"
     config.good_job.cron = {
       auto_upgrade: {
-        cron: "every 30 seconds",
+        cron: "every 2 minutes",
         class: "AutoUpgradeJob",
         description: "Check for new versions of the app and upgrade if necessary"
       }