Copy execution environment to Poseidon on create and update

When creating or updating an execution environment, an API call to
Poseidon is made with the necessary information to create the
corresponding Nomad job.

If runner management is configured, his will display a warning
(currently in the same color as if it were a success) in the UI, if the
API call fails. The environment is saved even if it fails.
If runner management is not configured, this warning will not be created.

db/migrate/20210601095654_add_cpu_limit_to_execution_environment.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddCpuLimitToExecutionEnvironment < ActiveRecord::Migration[6.1]
+  def change
+    add_column :execution_environments, :cpu_limit, :integer, default: 20
+  end
+end

db/migrate/20210602071834_clean_exposed_ports_in_execution_environment.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class CleanExposedPortsInExecutionEnvironment < ActiveRecord::Migration[6.1]
+  def change
+    ExecutionEnvironment.all.each do |execution_environment|
+      continue if execution_environment.exposed_ports.nil?
+
+      cleaned = execution_environment.exposed_ports.gsub(/[[:space:]]/, '')
+      list = cleaned.split(',').map(&:to_i).uniq
+      if list.empty?
+        execution_environment.update(exposed_ports: nil)
+      else
+        execution_environment.update(exposed_ports: list.join(','))
+      end
+    end
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2021_05_19_134938) do
+ActiveRecord::Schema.define(version: 2021_06_02_071834) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -112,6 +112,7 @@ ActiveRecord::Schema.define(version: 2021_05_19_134938) do
     t.integer "file_type_id"
     t.integer "memory_limit"
     t.boolean "network_enabled"
+    t.integer "cpu_limit"
   end
 
   create_table "exercise_collection_items", id: :serial, force: :cascade do |t|