Fixed typo.

Signed-off-by: Cristiano Urban <cristiano.urban@inaf.it>

transfer_service/tape_client.py

@@ -78,7 +78,7 @@ class TapeClient(object):
 
     def getHSMFilesystemList(self):
         """Returns a list containing all the available HSM filesystems."""
-        cmd = f"{self.DSMDF} -detail | grep \"HSM Filesystem\" | awk '{ print $3 }'"
+        cmd = f"{self.DSMDF} -detail | grep \"HSM Filesystem\" | awk '{{ print $3 }}'"
         try:
             stdin, stdout, stderr = self.client.exec_command(cmd)
         except Exception:
@@ -95,7 +95,7 @@ class TapeClient(object):
 
     def getHSMFilesystemFreeSpace(self, HSMFilesystem):
         "Returns the free space in bytes for a given HSM filesystem."
-        cmd = f"{self.DSMDF} -detail {HSMFilesystem} | grep "Free Size" | awk '{ print $3 }'"
+        cmd = f"{self.DSMDF} -detail {HSMFilesystem} | grep \"Free Size\" | awk '{{ print $3 }}'"
         try:
             stdin, stdout, stderr = self.client.exec_command(cmd)
         except Exception: