[report] check for symlink before rmtree when opt estimate-only is use

[slashdd]

Check if the dir is also symlink before performing using rmtree()
method, it not, then unlink() should be used.

Call Trace:
Finished running plugins Traceback (most recent call last):
File "./bin/sos", line 22, in
sos.execute()
File "/tmp/sos/sos/init.py", line 186, in execute
self._component.execute()
OSError: Cannot call rmtree on a symbolic link

/usr/lib/python3.8/shutil.py(726)rmtree()
-> raise OSError("Cannot call rmtree on a symbolic link")

Closes: #2727

Signed-off-by: Eric Desrochers eric.desrochers@canonical.com

---

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[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

⚠️ Please note that our current plans include removal of these comments in the near future (at least 2 weeks after including this disclaimer), if you have serious concerns regarding their removal or would like to continue receiving them please reach out to us. ⚠️

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-2728
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[slashdd]

With the PR, no more complaints about rmtree() method on symlink.

sudo python3 ./bin/sos report -o systemd --estimate-only

sosreport (version 4.2)

WARNING: unable to set option for disabled or non-existing plugin (networking).

This command will collect system configuration and diagnostic
information from this Ubuntu system.

For more information on Canonical visit:

        Community Website  : https://www.ubuntu.com/
        Commercial Support : https://www.canonical.com

The generated archive may contain data considered sensitive and its
content should be reviewed by the originating organization before being
passed to any third party.

No changes will be made to system configuration.



Estimate-only mode enabled, which overrides some options:
  --threads=4 overriden to 1
  --build enabled
  --no-postproc enabled

Press ENTER to continue, or CTRL-C to quit.

Optionally, please enter the case id that you are generating this report for []: 

 Setting up archive ...
 Setting up plugins ...
 Running plugins. Please wait ...

  Starting 1/1   systemd         [Running: systemd]                                       
  Finished running plugins                                                               
Skipping postprocessing of collected data

Your sosreport build tree has been generated in:
	/tmp/sosreport-nuc7-2021-10-19-cwcosbe


Estimated disk space requirement for whole uncompressed sos report directory: 4.41MiB
Three biggest plugins:  systemd: 4MiB,  sos_logs_reports: 540KiB

Please note the estimation is relevant to the current options.
Be aware that the real disk space requirements might be different.