Merge torrust#760: dev: ci: enable rust stable workflows

0999aa0 dev: ci: enable rust stable workflows (Cameron Garnham)

Pull request description:

  closes: torrust#580

  Re-enabled Rust Stable in Workflows and Container Building.

ACKs for top commit:
  da2ce7:
    ACK 0999aa0

Tree-SHA512: c281b6bd92ce634325364e9c4c299c0f4f7f683ae1e0c1924765881a3e18ae85b025e238968e5ab00a60baf52cafe8e83228d8ecbb36cc165bb38efd6555ee57

.github/workflows/contract.yaml

@@ -14,7 +14,7 @@ jobs:
 
     strategy:
       matrix:
-        toolchain: [nightly]
+        toolchain: [nightly, stable]
 
     steps:
       - id: checkout

.github/workflows/deployment.yaml

@@ -12,7 +12,7 @@ jobs:
 
     strategy:
       matrix:
-        toolchain: [nightly]
+        toolchain: [nightly, stable]
 
     steps:
       - id: checkout

.github/workflows/testing.yaml

@@ -39,7 +39,7 @@ jobs:
 
     strategy:
       matrix:
-        toolchain: [nightly]
+        toolchain: [nightly, stable]
 
     steps:
       - id: checkout
@@ -93,7 +93,7 @@ jobs:
 
     strategy:
       matrix:
-        toolchain: [nightly]
+        toolchain: [nightly, stable]
 
     steps:
       - id: checkout
@@ -132,7 +132,7 @@ jobs:
 
     strategy:
       matrix:
-        toolchain: [nightly]
+        toolchain: [nightly, stable]
 
     steps:
       - id: setup

Containerfile

@@ -3,13 +3,13 @@
 # Torrust Tracker
 
 ## Builder Image
-FROM rustlang/rust:nightly-bookworm as chef
+FROM docker.io/library/rust:bookworm as chef
 WORKDIR /tmp
 RUN curl -L --proto '=https' --tlsv1.2 -sSf https://raw.githubusercontent.com/cargo-bins/cargo-binstall/main/install-from-binstall-release.sh | bash
 RUN cargo binstall --no-confirm cargo-chef cargo-nextest
 
 ## Tester Image
-FROM rustlang/rust:nightly-bookworm-slim as tester
+FROM docker.io/library/rust:slim-bookworm as tester
 WORKDIR /tmp
 
 RUN apt-get update; apt-get install -y curl sqlite3; apt-get autoclean