Try to fix URL lookup errors

src/joann-pupper-bot/reddit.cr

@@ -21,7 +21,7 @@ class RedditResponse
     children: Array(RedditWrapper(RedditChild)))
 
   def self.from_subreddits(subreddits : Array(String))
-    request_url = "https://www.reddit.com/r/#{subreddits.join "+" }/hot.json?limit=30"
+    request_url = URI.new scheme: "https", host: "www.reddit.com", path: "/r/hot.json", query: "limit=30"
     response = HTTP::Client.get(request_url, headers: HTTP::Headers {
       "User-agent" => "Joann-Pupper-Bot"
     })
@@ -53,7 +53,8 @@ def filter_reddit_json(json, completed, extensions = ["png", "json"])
 end
 
 def get_reddit_post(subreddit, completed)
-    json = RedditResponse.from_subreddit subreddit
-    post = json.try { |json| filter_reddit_json(json, completed).first? }
-    post.try { |post| completed.push(post.name); { post.url, post.title } }
+    return nil unless json = RedditResponse.from_subreddit subreddit
+    return nil unless post = filter_reddit_json(json, completed).first?
+    completed.push(post.name)
+    return { post.url, post.title }
 end