chore(kinesis): don't log an error when kinesis payload isn't json (#6995)

(this is a duplicate of the change in
#6970 but targeting 1.19).
We are using boto3 to push protobuf encoded data to kinesis. We noticed
the following error in our logs:

```
Unable to parse payload, unable to inject trace context.
```

It seems that any data that isn't json encoded will cause this error
message. I don't believe there's any requirement for data to be json
encoded so I believe this should not be an error level log.

## Checklist

- [x] Change(s) are motivated and described in the PR description.
- [x] Testing strategy is described if automated tests are not included
in the PR.
- [x] Risk is outlined (performance impact, potential for breakage,
maintainability, etc).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] [Library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
are followed. If no release note is required, add label
`changelog/no-changelog`.
- [x] Documentation is included (in-code, generated user docs, [public
corp docs](https://github.com/DataDog/documentation/)).
- [x] Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist

- [x] Title is accurate.
- [x] No unnecessary changes are introduced.
- [x] Description motivates each change.
- [x] Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes unless absolutely necessary.
- [x] Testing strategy adequately addresses listed risk(s).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] Release note makes sense to a user of the library.
- [x] Reviewer has explicitly acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment.
- [x] Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)
- [x] If this PR touches code that signs or publishes builds or
packages, or handles credentials of any kind, I've requested a review
from `@DataDog/security-design-and-guidance`.
- [x] This PR doesn't touch any of that.

Co-authored-by: Munir Abdinur <[email protected]>

Author: meadsteve

ddtrace/contrib/botocore/patch.py

@@ -300,7 +300,7 @@ def get_kinesis_data_object(data):
     - json string
     - byte encoded json string
     - base64 encoded json string
-    If it's neither of these, then we leave the message as it is.
+    If it's none of these, then we leave the message as it is.
     """
 
     # check if data is a json string
@@ -321,7 +321,7 @@ def get_kinesis_data_object(data):
         data_str = base64.b64decode(data).decode("ascii")
         return get_json_from_str(data_str)
     except Exception:
-        log.error("Unable to parse payload, unable to inject trace context.")
+        log.debug("Unable to parse payload, unable to inject trace context.")
 
     return None, None