test(spans): Add sampling columns temporarily (#77789)

- This adds the sampling columns to help explore the extrapolation data
better, We should not use this in the UI and its just for testing

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Co-authored-by: getsantry[bot] <66042841+getsantry[bot]@users.noreply.github.com>

src/sentry/utils/snuba.py

@@ -188,6 +188,9 @@ def log_snuba_info(content):
     # message also maps to span description but gets special handling
     # to support wild card searching by default
     "message": "name",
+    # These sample columns are for debugging only and shouldn't be used
+    "sampling_weight": "sampling_weight",
+    "sampling_factor": "sampling_factor",
     "span.domain": "attr_str[domain]",
     "span.group": "attr_str[group]",
     "span.op": "attr_str[op]",