fix: quoting for SLURM partition (#399)

Fixes TypeError when partition is an int. (TypeError: expected string or
bytes-like object, got 'int' from shlex.quote())

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## Summary by CodeRabbit

* **Bug Fixes**
* Safely handle SLURM partition inputs by converting non-string values
to strings before quoting, preventing errors when users provide numeric
or other non-string partition values and improving robustness of
partition handling.

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---------

Co-authored-by: Christian Meesters <cmeesters@users.noreply.github.com>

Author: patrickaoude

snakemake_executor_plugin_slurm/__init__.py

@@ -968,7 +968,8 @@ def get_partition_arg(self, job: JobExecutorInterface):
         if partition:
             # we have to quote the partition, because it might
             # contain build-in shell commands
-            return f" -p {shlex.quote(partition)}"
+            # string conversion needed for partition if partition is an integer
+            return f" -p {shlex.quote(str(partition))}"
         else:
             return ""