fix: SonarQube reliability issues.

- Fixed in `src/instana/instrumentation/aws/boto3.py`:
    - Low reliability issue **Function parameters initial values should
not be ignored.**
- Fixed in `src/instana/instrumentation/tornado/client.py`:
    - Medium reliability issue **All "except" blocks should be able to
catch exceptions.**

Signed-off-by: Paulo Vital <paulo.vital@ibm.com>

Author: pvital

src/instana/instrumentation/aws/boto3.py

@@ -23,7 +23,6 @@
 
     from instana.log import logger
     from instana.propagators.format import Format
-    from instana.singletons import get_tracer
     from instana.util.traceutils import extract_custom_headers, get_tracer_tuple
 
     def lambda_inject_context(
@@ -37,7 +36,6 @@ def lambda_inject_context(
         https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/lambda.html#Lambda.Client.invoke
         """
         try:
-            tracer = get_tracer()
             invoke_payload = payload.get("Payload", {})
 
             if not isinstance(invoke_payload, dict):

src/instana/instrumentation/tornado/client.py

@@ -102,5 +102,3 @@ def finish_tracing(future: "Future", span: "InstanaSpan") -> None:
     logger.debug("Instrumenting tornado client")
 except ImportError:
     pass
-except ImportError:
-    pass