use underscore separators for plugin slug (zip folder) (#277)

* use underscore separators for plugin slug (zip folder)

since we don't want dashes in folder names

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

qgispluginci/parameters.py

@@ -175,7 +175,7 @@ def __init__(self, definition: Dict[str, Any]):
 
         get_metadata = self.collect_metadata()
         self.plugin_name = get_metadata("name")
-        self.plugin_slug = slugify(self.plugin_name)
+        self.plugin_slug = slugify(self.plugin_name, separator="_")
 
         # fix directory in zip file
         self.use_project_slug_as_plugin_directory = definition.get(