Remove redundant '(a text string)' from cssText docstrings

Agent-Logs-Url: https://github.com/jaraco/cssutils/sessions/0ce2b23e-e394-40c4-8bb8-0172e0728a69

Co-authored-by: jaraco <308610+jaraco@users.noreply.github.com>

Author: Copilot

cssutils/css/cssstylesheet.py

@@ -146,7 +146,7 @@ def cssRules(self, cssRules):
         self._cssRules = cssRules
 
     def _getCssText(self):
-        "Textual representation of the stylesheet (a text string)."
+        "Textual representation of the stylesheet."
         return cssutils.ser.do_CSSStyleSheet(self)
 
     def _setCssText(self, cssText):  # noqa: C901
@@ -361,7 +361,7 @@ def ruleset(expected, seq, token, tokenizer):
     cssText = property(
         _getCssText,
         _setCssText,
-        "Textual representation of the stylesheet (a text string)",
+        "Textual representation of the stylesheet",
     )
 
     def _resolveImport(self, url):