bazel: fix opentelemetry-cpp warning (#32624)

Fixes #32591

Signed-off-by: Keith Smiley <keithbsmiley@gmail.com>

bazel/io_opentelemetry_cpp.patch

@@ -0,0 +1,13 @@
+# TODO: Remove once https://github.com/open-telemetry/opentelemetry-cpp/issues/2556 is merged
+
+--- a/api/include/opentelemetry/trace/span_context.h
++++ b/api/include/opentelemetry/trace/span_context.h
+@@ -30,7 +30,7 @@ class SpanContext final
+   SpanContext(bool sampled_flag, bool is_remote) noexcept
+       : trace_id_(),
+         span_id_(),
+-        trace_flags_(trace::TraceFlags((uint8_t)sampled_flag)),
++        trace_flags_(trace::TraceFlags(static_cast<uint8_t>(sampled_flag))),
+         is_remote_(is_remote),
+         trace_state_(TraceState::GetDefault())
+   {}

bazel/repositories.bzl

@@ -777,7 +777,11 @@ def _io_opentracing_cpp():
     )
 
 def _io_opentelemetry_api_cpp():
-    external_http_archive("io_opentelemetry_cpp")
+    external_http_archive(
+        name = "io_opentelemetry_cpp",
+        patch_args = ["-p1"],
+        patches = ["@envoy//bazel:io_opentelemetry_cpp.patch"],
+    )
     native.bind(
         name = "opentelemetry_api",
         actual = "@io_opentelemetry_cpp//api:api",