build: install nightly and v1.74.1 directly in dockerfile

Switching test from 1.81.0 to 1.74.1 to match an MSRV that I actually use.

.forgejo/workflows/test.yml

@@ -10,7 +10,7 @@ jobs:
         toolchain:
           - name: stable
           - name: nightly
-          - name: v1.81.0
+          - name: v1.74.1
 
     steps:
       - uses: actions/checkout@v4

Dockerfile

@@ -27,12 +27,14 @@ RUN cargo binstall -y \
   cargo-mutants@25.0 \
   release-plz@0.3
 
-COPY update.sh /
-
 # should be a no-op if the FROM line is up-to-date
-RUN /update.sh stable 
+RUN rustup update stable && rustup component add --toolchain stable rustfmt clippy
 
-RUN rustup install nightly && /update.sh nightly
+# install nightly
+RUN rustup install nightly && rustup component add --toolchain nightly rustfmt clippy
+
+# install v1.74.1
+RUN rustup install 1.74.1 && rustup component add --toolchain 1.74.1 rustfmt clippy
 
 COPY entrypoint.sh /
 

update.sh

@@ -1,32 +0,0 @@
-#!/usr/bin/env bash
-
-set -e
-
-echo "INPUT_ARGS: ${INPUT_ARGS}"
-
-# split input into an array
-read -ra ARGS <<<"${INPUT_ARGS}"
-
-# default toolchain
-TOOLCHAIN="stable"
-echo "Default toolchain: ${TOOLCHAIN}"
-
-# if first parameter is 'nightly'...
-if test "${ARGS[0]}" == "nightly"; then
-  TOOLCHAIN="nightly"
-  ARGS=("${ARGS[@]:1}")
-fi
-if test "${ARGS[0]}" == "stable"; then
-  TOOLCHAIN="stable" # redundant as this is the default
-  ARGS=("${ARGS[@]:1}")
-fi
-if [[ "${ARGS[0]}" == v1* ]]; then
-  TOOLCHAIN="${ARGS[0]:1}"
-  ARGS=("${ARGS[@]:1}")
-fi
-echo "Selected toolchain: ${TOOLCHAIN}"
-
-echo ">>> Update toolchain"
-rustup update "${TOOLCHAIN}"
-echo ">>> Install rustfmt and clippy"
-rustup component add --toolchain "${TOOLCHAIN}" rustfmt clippy