docs: update trace filter docs [backport 2.20] (#12149)

Backport 8ff2ecb from #12147 to 2.20.

Resolves: #12141

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Co-authored-by: Munir Abdinur <[email protected]>

Author: github-actions[bot]

docs/advanced_usage.rst

@@ -342,11 +342,7 @@ all traces of incoming requests to a specific url::
                     return None
             return trace
 
-    tracer.configure(settings={
-        'FILTERS': [
-            FilterbyName(),
-        ],
-    })
+    tracer.configure(trace_processors=[FilterbyName()])
 
 The filters in the filters list will be applied sequentially to each trace
 and the resulting trace will either be sent to the Agent or discarded.
@@ -367,7 +363,7 @@ the pipeline or ``None`` if the trace should be discarded::
             ...
 
     # And then configure it with
-    tracer.configure(settings={'FILTERS': [FilterExample()]})
+    tracer.configure(trace_processors=[FilterExample()])
 
 (see filters.py for other example implementations)
 

docs/troubleshooting.rst

@@ -91,7 +91,7 @@ While this is default behavior for integrations, users can add a trace filter to
         return trace
 
 
-  tracer.configure(settings={'FILTERS': [ErrorFilter()]})
+  tracer.configure(trace_processors=[ErrorFilter()])