[Python Otel] Remove opentelemetry version pin (#36448)

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Closes #36448

PiperOrigin-RevId: 629113962

examples/python/observability/requirements.txt

@@ -1,3 +1,3 @@
 grpcio>=1.62.0
 grpcio-observability>=1.62.0
-opentelemetry-sdk==1.21.0
+opentelemetry-sdk>=1.21.0

src/python/grpcio_observability/grpc_observability/BUILD.bazel

@@ -53,7 +53,7 @@ pyx_library(
     ],
 )
 
-# Since `opentelemetry-sdk` and `opentelemetry-api` are non-hermetic,
+# Since `opentelemetry-api` is non-hermetic,
 # pyobservability is for internal use only.
 py_library(
     name = "_opentelemetry_observability",
@@ -63,7 +63,6 @@ py_library(
         "_open_telemetry_plugin.py",
     ],
     deps = [
-        requirement("opentelemetry-sdk"),
         requirement("opentelemetry-api"),
     ],
 )

src/python/grpcio_observability/setup.py

@@ -290,7 +290,7 @@ setuptools.setup(
     install_requires=[
         "grpcio=={version}".format(version=grpc_version.VERSION),
         "setuptools>=59.6.0",
-        "opentelemetry-api==1.21.0",
+        "opentelemetry-api>=1.21.0",
     ],
     cmdclass={
         "build_ext": BuildExt,

src/python/grpcio_tests/tests/observability/BUILD.bazel

@@ -11,6 +11,9 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+load("@grpc_python_dependencies//:requirements.bzl", "requirement")
+
 package(default_visibility = ["//visibility:public"])
 
 py_library(
@@ -34,6 +37,7 @@ py_test(
         "//src/python/grpcio/grpc:grpcio",
         "//src/python/grpcio_observability/grpc_observability:pyobservability",
         "//src/python/grpcio_tests/tests/testing",
+        requirement("opentelemetry-sdk"),
     ],
 )