fs-backup-timeout argument is not taking string value in DPA

Description of problem:

When fs-backup-timeout is tried to set as 120m as string value as per velero document in DPA as below then it is throwing error:

DPA:

~~~

apiVersion: oadp.openshift.io/v1alpha1
kind: DataProtectionApplication
metadata:
  name: velero
  namespace: openshift-adp
spec:
  [..]
  configuration:
    [..]
    velero:
      args:
        fs-backup-timeout: 120m
~~~

Error:

~~~

spec.configuration.velero.args.fs-backup-timeout: Invalid value: "string": spec.configuration.velero.args.fs-backup-timeout in body must be of type integer: "string"
~~~

If we set only integer value like 120 then velero deployment gets set with 120ns i.e. nanosecond which would be too low.

Velero deployment if we set integer value:

~~~
   spec:
      containers:
      - args:
        - server
        - --fs-backup-timeout=120ns

~~~

When we set fs-backup-timeout: 7200000000000 then velero deployment gets set as 2 hours.

~~~

   spec:
      containers:
      - args:
        - server
        - --fs-backup-timeout=2h0m0s
~~~

Version-Release number of selected component (if applicable):

How reproducible: Always

Steps to Reproduce:
1. Try to add fs-backup-timeout argument as 120m or 2h in DPA for velero configuration as shown in description with oc edit dpa command.
2. Edit will fail and show the error.

Actual results:

DPA edit fails if we mention string value for fs-backup-timeout argument and only accepts integer value. If integer value is set then velero deployment takes it as nanoseconds.

Expected results:

DPA should allow mentioning string values for fs-backup-timeout argument in velero configuration which are easy to set like 120m i.e. 120 minutes or 2h i.e. 2 hours. This is allowed in actual velero deployment.

Additional info: