Update rust Docker tag to v1.75 (#38)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| rust | stage | minor | `1.72-slim-buster` -> `1.75-slim-buster` |

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Dockerfile

@@ -1,4 +1,4 @@
-FROM rust:1.72-slim-buster as build
+FROM rust:1.75-slim-buster as build
 # Found at https://dev.to/rogertorres/first-steps-with-docker-rust-30oi
 
 # create a new empty shell project