[BUG] 3002.5 influxdb_retention_policy.present state, convert_duration hours

Description
If the influxdb_retention_policy.present state is run with the duration specified in hours, and the retention policy already exists, the state will fail. If the retention policy isn't preexisting it will be created, but the state will fail the next run due to it existing as previously mentioned.

Setup

set_autogen_retention_policy:
  influxdb_retention_policy.present:
    - name: autogen
    - database: telegraf
    - duration: 2h
    - replication: 1
    - default: True

Steps to Reproduce the behavior
Create the state above and apply it. If the retention policy doesn't exist, it will be created. If it does exist, the following error will be seen:

     Comment: An exception occurred in this state: Traceback (most recent call last):
                File "/usr/lib/python3.6/site-packages/salt/state.py", line 2154, in call
                  *cdata["args"], **cdata["kwargs"]
                File "/usr/lib/python3.6/site-packages/salt/loader.py", line 2106, in wrapper
                  return f(*args, **kwargs)
                File "/usr/lib/python3.6/site-packages/salt/states/influxdb_retention_policy.py", line 92, in present
                  if current_policy["duration"] != convert_duration(duration):
                File "/usr/lib/python3.6/site-packages/salt/states/influxdb_retention_policy.py", line 38, in convert_duration
                  hours = int(duration.split("h"))
              TypeError: int() argument must be a string, a bytes-like object or a number, not 'list'

The issue can bee seen in the code at line 38 in /usr/lib/python3.6/site-packages/salt/states/influxdb_retention_policy.py:
hours = int(duration.split("h")) should be hours = int(duration.split("h")[0])

Expected behavior
I expect nothing to happen if the retention policy already exists and the duration specified in the state matches the duration in InfluxDB. If the RP exists, but the durations don't match, it should be updated.

Versions Report

Salt Version:
          Salt: 3002.5

Dependency Versions:
          cffi: Not Installed
      cherrypy: Not Installed
      dateutil: 2.8.1
     docker-py: 2.6.1
         gitdb: Not Installed
     gitpython: Not Installed
        Jinja2: 2.11.1
       libgit2: Not Installed
      M2Crypto: 0.35.2
          Mako: Not Installed
       msgpack: 0.6.2
  msgpack-pure: Not Installed
  mysql-python: 1.3.12
     pycparser: Not Installed
      pycrypto: Not Installed
  pycryptodome: Not Installed
        pygit2: Not Installed
        Python: 3.6.8 (default, Nov 16 2020, 16:55:22)
  python-gnupg: Not Installed
        PyYAML: 3.13
         PyZMQ: 17.0.0
         smmap: Not Installed
       timelib: Not Installed
       Tornado: 4.5.3
           ZMQ: 4.1.4

System Versions:
          dist: centos 7 Core
        locale: UTF-8
       machine: x86_64
       release: 3.10.0-1160.15.2.el7.x86_64
        system: Linux
       version: CentOS Linux 7 Core

Start in salt/states/influxdb_retention_policy.py at convert_duration and the present state path that compares an existing policy's duration. Reproduce the reported failure with a duration such as 2h, then verify that an existing matching retention policy completes successfully and that a differing duration still follows the update behavior described in the issue.