fix type

Author: sentrivana

sentry_sdk/integrations/opentelemetry/sampler.py

@@ -51,14 +51,18 @@ def get_parent_sampled(parent_context, trace_id):
 
 
 def get_parent_sample_rate(parent_context, trace_id):
-    # type: (Optional[SpanContext], int) -> Optional[bool]
+    # type: (Optional[SpanContext], int) -> Optional[float]
     if parent_context is None:
         return None
 
     is_span_context_valid = parent_context is not None and parent_context.is_valid
 
     if is_span_context_valid and parent_context.trace_id == trace_id:
-        return parent_context.trace_state.get(TRACESTATE_SAMPLE_RATE_KEY)
+        parent_sample_rate = parent_context.trace_state.get(TRACESTATE_SAMPLE_RATE_KEY)
+        try:
+            parent_sample_rate = float(parent_sample_rate)
+        except Exception:
+            return None
 
     return None