Update default enabled state for ca2025.md

We make the new analyzer opt-in for now: dotnet/roslyn-analyzers#7689

Author: akoeplinger

docs/fundamentals/code-analysis/quality-rules/ca2025.md

@@ -21,7 +21,7 @@ dev_langs:
 | **Title**                           | Do not pass 'IDisposable' instances into unawaited tasks |
 | **Category**                        | [Reliability](reliability-warnings.md)               |
 | **Fix is breaking or non-breaking** | Non-breaking                                         |
-| **Enabled by default in .NET 10**   | As warning                                           |
+| **Enabled by default in .NET 10**   | No                                                   |
 
 ## Cause