fix(deps): update module go.opentelemetry.io/contrib/bridges/otelslog to v0.21.0 (#993)

This PR contains the following updates:

| Package | Change | [Age](https://docs.renovatebot.com/merge-confidence/) | [Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [go.opentelemetry.io/contrib/bridges/otelslog](https://github.com/open-telemetry/opentelemetry-go-contrib) | `v0.20.1` → `v0.21.0` | ![age](https://developer.mend.io/api/mc/badges/age/go/go.opentelemetry.io%2fcontrib%2fbridges%2fotelslog/v0.21.0?slim=true) | ![confidence](https://developer.mend.io/api/mc/badges/confidence/go/go.opentelemetry.io%2fcontrib%2fbridges%2fotelslog/v0.20.1/v0.21.0?slim=true) |

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### Release Notes

<details>
<summary>open-telemetry/opentelemetry-go-contrib (go.opentelemetry.io/contrib/bridges/otelslog)</summary>

### [`v0.21.0`](https://github.com/open-telemetry/opentelemetry-go-contrib/releases/tag/v0.21.0)

#### 0.21.0 - 2021-06-18

##### Fixed

- Dockerfile based examples for `otelgin` and `otelmacaron`. ([#&#8203;767](https://github.com/open-telemetry/opentelemetry-go-contrib/issues/767))

##### Changed

- Supported minimum version of Go bumped from 1.14 to 1.15. ([#&#8203;787](https://github.com/open-telemetry/opentelemetry-go-contrib/issues/787))
- EKS Resource Detector now use the Kubernetes Go client to obtain the ConfigMap. ([#&#8203;813](https://github.com/open-telemetry/opentelemetry-go-contrib/issues/813))

##### Removed

- Remove service name from `otelmongodb` configuration and span attributes. ([#&#8203;763](https://github.com/open-telemetry/opentelemetry-go-contrib/issues/763))

</details>

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Reviewed-on: https://git.unbound.se/unboundsoftware/schemas/pulls/993
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go.mod

@@ -21,7 +21,7 @@ require (
 	github.com/stretchr/testify v1.12.1
 	github.com/vektah/gqlparser/v2 v2.5.60
 	github.com/wundergraph/graphql-go-tools/v2 v2.26.0
-	go.opentelemetry.io/contrib/bridges/otelslog v0.20.1
+	go.opentelemetry.io/contrib/bridges/otelslog v0.21.0
 	go.opentelemetry.io/otel v1.47.0
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.47.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.47.0