ci: Explicitly select stable Rust version

And for now we stay at 1.46.0 because 1.47.0 has a bug that prevents
clippy from succeeding.

.gitlab-ci.yml

@@ -2,7 +2,7 @@
 # to build the images used by the ci.
 #
 # Here is how to properly update thoses images:
-# - new Rust stable version: update GST_RS_IMG_TAG
+# - new Rust stable version: update GST_RS_IMG_TAG and update Rust version
 # - add dependencies: update FDO_DISTRIBUTION_PACKAGES and update GST_RS_IMG_TAG
 # - update GStreamer version: update the tag in ci/install-gst.sh and update GST_RS_IMG_TAG
 #
@@ -61,7 +61,8 @@ stages:
 .debian:10-stable:
   extends: .debian:10
   variables:
-    RUST_VERSION: "stable"
+    RUST_VERSION: "1.46.0"
+    RUST_IMAGE_FULL: "1"
 
 .debian:10-1-41:
   extends: .debian:10
@@ -87,7 +88,7 @@ stages:
   stage: container-final
   variables:
     FDO_BASE_IMAGE: '$CI_REGISTRY_IMAGE/debian/10:base-$GST_RS_IMG_TAG'
-    FDO_DISTRIBUTION_EXEC: 'bash ci/install-rust.sh $RUST_VERSION'
+    FDO_DISTRIBUTION_EXEC: 'bash ci/install-rust.sh $RUST_VERSION $RUST_IMAGE_FULL'
 
 build-base:
   extends:

ci/images_template.yml

@@ -1,2 +1,2 @@
 variables:
-  GST_RS_IMG_TAG: '2020-09-09.0'
+  GST_RS_IMG_TAG: '2020-10-31.0'

ci/install-rust.sh

@@ -5,6 +5,7 @@ export CARGO_HOME='/usr/local/cargo'
 
 RUSTUP_VERSION=1.22.1
 RUST_VERSION=$1
+RUST_IMAGE_FULL=$2
 RUST_ARCH="x86_64-unknown-linux-gnu"
 
 RUSTUP_URL=https://static.rust-lang.org/rustup/archive/$RUSTUP_VERSION/$RUST_ARCH/rustup-init
@@ -19,7 +20,7 @@ rustup --version
 cargo --version
 rustc --version
 
-if [ "$RUST_VERSION" = "stable" ]; then
+if [ "$RUST_IMAGE_FULL" = "1" ]; then
   rustup component add clippy-preview
   rustup component add rustfmt
   cargo install --force cargo-deny