Fix Thread leakage when scoring or testing submissions

It is discouraged to do anything directly within the
Tubesock hijack block. We might only use the callbacks
(onopen, onmessage, onclose, onerror). Otherwise,
Tubesock might not close all Threads correctly and
will keep them awake every five seconds.

Gemfile.lock

@@ -6,15 +6,6 @@ GIT
       json (~> 2.6.1)
       structured_warnings (~> 0.4.0)
 
-GIT
-  remote: https://github.com/gosukiwi/tubesock.git
-  revision: 86a5ca4f7d3c3a7b9a727ad91df3b9b4912eda39
-  branch: patch-1
-  specs:
-    tubesock (0.2.7)
-      rack (>= 1.5.0)
-      websocket (>= 1.1.0)
-
 GIT
   remote: https://github.com/openHPI/proforma.git
   revision: dc68000325388e1d75f31be9e136a82edad8a56d
@@ -162,7 +153,7 @@ GEM
       regexp_parser (~> 2.2)
     erubi (1.10.0)
     eventmachine (1.2.7)
-    excon (0.92.1)
+    excon (0.92.2)
     factory_bot (6.2.1)
       activesupport (>= 5.0.0)
     factory_bot_rails (6.2.0)
@@ -238,7 +229,7 @@ GEM
     listen (3.7.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
-    loofah (2.15.0)
+    loofah (2.16.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)
@@ -264,7 +255,7 @@ GEM
     mnemosyne-ruby (1.12.1)
       activesupport (>= 4)
       bunny
-    msgpack (1.4.5)
+    msgpack (1.5.1)
     multi_json (1.15.0)
     multi_xml (0.6.0)
     nested_form (0.3.2)
@@ -287,7 +278,7 @@ GEM
       rack (>= 1.2, < 3)
     pagedown-bootstrap-rails (2.1.4)
       railties (> 3.1)
-    parallel (1.22.0)
+    parallel (1.22.1)
     parser (3.1.1.0)
       ast (~> 2.4.1)
     path_expander (1.1.0)
@@ -397,7 +388,7 @@ GEM
     rspec-expectations (3.11.0)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.11.0)
-    rspec-mocks (3.11.0)
+    rspec-mocks (3.11.1)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.11.0)
     rspec-rails (5.1.1)
@@ -495,6 +486,9 @@ GEM
     temple (0.8.2)
     thor (1.2.1)
     tilt (2.0.10)
+    tubesock (0.2.9)
+      rack (>= 1.5.0)
+      websocket (>= 1.1.0)
     turbolinks (5.2.1)
       turbolinks-source (~> 5.2)
     turbolinks-source (5.2.0)
@@ -603,7 +597,7 @@ DEPENDENCIES
   sorcery
   spring
   telegraf
-  tubesock!
+  tubesock
   turbolinks
   web-console
   webmock