build(deps): bump apache/skywalking-ui in /skywalking (#194)

Bumps apache/skywalking-ui from `6e87fcd` to `fc2b398`.

---
updated-dependencies:
- dependency-name: apache/skywalking-ui
  dependency-type: direct:production
...

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

skywalking/Dockerfile-skywalking-ui

@@ -1 +1 @@
-FROM apache/skywalking-ui:latest@sha256:6e87fcdaa13ef3cac4d1fc482422987461c9d6b79b661f2fa80bf16a271022b8
+FROM apache/skywalking-ui:latest@sha256:fc2b398ffe65ec4da4a39b6e5f9e0abd4992373c70503604f3a2efe928b1560f