Unable to calibrate any labware with Thermocycler in protocol

[mcous]

overview

#4441 switched the data structure of the hardware controller's API::_attached_modules from a dictionary to a List in PAPIv2.

#4454 added logic to ProtocolContext::temp_connect to account for thermocyclers. It assumes, incorrectly, that API::attached_modules is still a dictionary, resulting in the following raise if you attemp to execute an RPC move_to

opentrons-api[322]: Moving p50_single_v1.3 to opentrons_96_tiprack_300ul in 1
opentrons-api[322]: Exception during RPC call:
  Traceback (most recent call last):
    File "usr/lib/python3.7/site-packages/opentrons/server/rpc.py", line 270, in make_call
    File "usr/lib/python3.7/concurrent/futures/thread.py", line 57, in run
    File "usr/lib/python3.7/site-packages/opentrons/server/rpc.py", line 260, in call_and_serialize
    File "usr/lib/python3.7/site-packages/opentrons/api/calibration.py", line 37, in decorated
    File "usr/lib/python3.7/site-packages/opentrons/api/calibration.py", line 53, in decorated
    File "usr/lib/python3.7/site-packages/opentrons/api/calibration.py", line 222, in move_to
    File "/buildroot/output/target/usr/lib/python3.7/contextlib.py", line 112, in __enter__
    File "usr/lib/python3.7/site-packages/opentrons/protocol_api/contexts.py", line 250, in temp_connect

current behavior

• Cannot move to labware during labware calibration if protocol has thermocycler

steps to reproduce

1. Load protocol with thermocycler
2. Attempt to calibrate labware
3. Robot will not move, app will not pop up calibration UI because robot responds with move failure