fix: copy tags dict before deleting span.kind to avoid caller mutation

Author: Nik-Reddy

shim/opentelemetry-opentracing-shim/src/opentelemetry/shim/opentracing_shim/__init__.py

@@ -676,6 +676,7 @@ def start_span(
             mapped_kind = util.opentracing_kind_to_otel_kind(tags["span.kind"])
             if mapped_kind is not None:
                 kind = mapped_kind
+            tags = dict(tags)
             del tags["span.kind"]
 
         # The OpenTracing API expects time values to be `float` values which