Add connection.disconnect() in finally blocks (#2189)

core/src/main/java/google/registry/tmch/Marksdb.java

@@ -121,6 +121,8 @@ public final class Marksdb {
       return getResponseBytes(connection);
     } catch (IOException e) {
       throw new IOException(String.format("Error connecting to MarksDB at URL %s", url), e);
+    } finally {
+      connection.disconnect();
     }
   }
 

core/src/main/java/google/registry/tmch/NordnUploadAction.java

@@ -225,6 +225,8 @@ public final class NordnUploadAction implements Runnable {
       cloudTasksUtils.enqueue(NordnVerifyAction.QUEUE, makeVerifyTask(new URL(location)));
     } catch (IOException e) {
       throw new IOException(String.format("Error connecting to MarksDB at URL %s", url), e);
+    } finally {
+      connection.disconnect();
     }
   }
 

core/src/main/java/google/registry/tmch/NordnVerifyAction.java

@@ -148,6 +148,8 @@ public final class NordnVerifyAction implements Runnable {
       return log;
     } catch (IOException e) {
       throw new IOException(String.format("Error connecting to MarksDB at URL %s", url), e);
+    } finally {
+      connection.disconnect();
     }
   }
 }