Bump com.gradleup.shadow from 8.3.6 to 8.3.8 in /performance-test (#5947)

Bumps [com.gradleup.shadow](https://github.com/GradleUp/shadow) from 8.3.6 to 8.3.8.
- [Release notes](https://github.com/GradleUp/shadow/releases)
- [Commits](GradleUp/shadow@8.3.6...8.3.8)

---
updated-dependencies:
- dependency-name: com.gradleup.shadow
  dependency-version: 8.3.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

performance-test/build.gradle

@@ -6,7 +6,7 @@
 plugins {
     id 'java'
     id 'io.gatling.gradle' version '3.10.4'
-    id 'com.gradleup.shadow' version '8.3.6'
+    id 'com.gradleup.shadow' version '8.3.8'
 }
 
 configurations.all {