chore(tracing): remove runtime import of asm config in Pin.enabled (#13578)

We need to avoid this as much as possible. I couldn't find the circular
import/reason why it was done that way.

This _should_ have a benefit for performance, but local benchmarks
showed it mostly flat, so maybe only a micro optimization, but still
good behavior.

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## Reviewer Checklist
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Author: brettlangdon

ddtrace/_trace/pin.py

@@ -6,6 +6,7 @@
 import wrapt
 
 import ddtrace
+from ddtrace.settings.asm import config as asm_config
 
 from ..internal.logger import get_logger
 
@@ -174,12 +175,8 @@ def _override(
             pin._tracer = tracer
         pin.onto(obj)
 
-    def enabled(self):
-        # type: () -> bool
+    def enabled(self) -> bool:
         """Return true if this pin's tracer is enabled."""
-        # inline to avoid circular imports
-        from ddtrace.settings.asm import config as asm_config
-
         return bool(self.tracer) and (self.tracer.enabled or asm_config._apm_opt_out)
 
     def onto(self, obj, send=True):