[full] Rust: Install minimal toolchain (e.g. without the HTML docs)

Source: rust-lang/rustup#998 (comment)

Author: jankeromnes

full/Dockerfile

@@ -247,11 +247,7 @@ LABEL dazzle/layer=lang-rust
 LABEL dazzle/test=tests/lang-rust.yaml
 USER gitpod
 RUN cp /home/gitpod/.profile /home/gitpod/.profile_orig && \
-    curl -fsSL https://sh.rustup.rs | sh -s -- -y \
-    && .cargo/bin/rustup toolchain install 1.48.0 \
-    && .cargo/bin/rustup default 1.48.0 \
-    # Save image size by removing now-redudant stable toolchain
-    && .cargo/bin/rustup toolchain uninstall stable \
+    curl -fsSL https://sh.rustup.rs | sh -s -- -y --profile minimal --default-toolchain 1.48.0 \
     && .cargo/bin/rustup component add \
         rls \
         rust-analysis \