fence_aws: clarify Python version requirement for boto3 dependency

[mrmitkov]

Description

In environments like SLES 15, boto3 is only available for a specific Python version (e.g. python3.11), while fence_aws may still use a different interpreter (/usr/bin/python3).

This can lead to runtime errors such as:
NameError: name 'boto3' is not defined

Suggestion

It would be helpful to clarify:

• the required Python version
• or the expected boto3 package variant
• or ensure the script uses a compatible interpreter

Environment

• OS: SLES 15 SP7
• fencing: fence_aws

### Error output
```bash
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [ Traceback (most recent call last): ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [   File "/usr/sbin/fence_aws", line 261, in <module> ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [     main() ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [   File "/usr/sbin/fence_aws", line 232, in main ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [     boto3.set_stream_logger('boto3',logging.INFO) ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_op_output)    info: fence_aws_monitor_2of2[2595063] error output [ NameError: name 'boto3' is not defined ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [ Traceback (most recent call last): ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [   File "/usr/sbin/fence_aws", line 261, in <module> ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [     main() ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [   File "/usr/sbin/fence_aws", line 232, in main ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [     boto3.set_stream_logger('boto3',logging.INFO) ]
Jun 11 11:52:52.079 HDB01 pacemaker-fenced    [19663] (log_action)       warning: fence_aws[2595063] stderr: [ NameError: name 'boto3' is not defined ]
---

[oalbrigt]

This is distribution specific, so not sure how we'd do that in a sensible way.

I would suggest reporting it to Suse, so they can solve it, and they're welcome to give us any suggestions for how we can improve this as well.