chore(deps): update golang:1.26 docker digest to fcdb3e4 (#102)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | digest | `ec4debb` → `fcdb3e4` |

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otlp-bench/bench-setup/Dockerfile.custom

@@ -3,7 +3,7 @@ FROM alpine:3.23@sha256:25109184c71bdad752c8312a8623239686a9a2071e8825f20acb8f21
 RUN apk --update add ca-certificates
 
 
-FROM golang:1.26@sha256:ec4debba7b371fb2eaa6169a72fc61ad93b9be6a9ae9da2a010cb81a760d36e7 AS build-stage
+FROM golang:1.26@sha256:fcdb3e42c5544e9682a635771eac76a698b66de79b1b50ec5b9ce5c5f14ad775 AS build-stage
 
 WORKDIR /build