chore(deps): update docker.io/rust docker tag to v1.94 (open-telemetry#2238)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker.io/rust | stage | minor | `1.93` → `1.94` |

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rust/otap-dataflow/Dockerfile

@@ -7,7 +7,7 @@
 # with the arrow enabled go collector build files in the repo root, the image
 # must be built with additional --build-context flags as follows:
 # docker build --build-context otel-arrow=../../ -f Dockerfile -t df_engine .
-FROM --platform=$BUILDPLATFORM docker.io/rust:1.93@sha256:51c04d7a2b38418ba23ecbfb373c40d3bd493dec1ddfae00ab5669527320195e AS dataflow-build
+FROM --platform=$BUILDPLATFORM docker.io/rust:1.94@sha256:0e6da0c8f06f25e9591f21c0f741cd4ff1086e271c3330f29f6e4e95869c7843 AS dataflow-build
 WORKDIR /build/rust/dataflow
 ARG BUILDPLATFORM
 ARG TARGETPLATFORM