Bump StackExchange.Redis from 2.2.88 to 2.6.80 (#230)

Bumps [StackExchange.Redis](https://github.com/StackExchange/StackExchange.Redis) from 2.2.88 to 2.6.80.
- [Release notes](https://github.com/StackExchange/StackExchange.Redis/releases)
- [Changelog](https://github.com/StackExchange/StackExchange.Redis/blob/main/docs/ReleaseNotes.md)
- [Commits](https://github.com/StackExchange/StackExchange.Redis/commits/2.6.80)

---
updated-dependencies:
- dependency-name: StackExchange.Redis
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/common.props

@@ -46,7 +46,7 @@ Other Changes**
     <XunitVersion>2.4.2</XunitVersion>
     <TestSdkVersion>17.4.0</TestSdkVersion>
     <AkkaVersion>1.4.46</AkkaVersion>
-    <RedisVersion>2.2.88</RedisVersion>
+    <RedisVersion>2.6.80</RedisVersion>
     <DockerVersion>3.125.12</DockerVersion>
     <NetCoreTestVersion>netcoreapp3.1</NetCoreTestVersion>
     <NetStandardVersion>netstandard2.0</NetStandardVersion>