packaging: Move builds to Ubuntu 22.04

As Ubuntu 20.04 will reach its EOL in April.

Signed-off-by: Fabiano Fidêncio <fabiano@fidencio.org>

tools/packaging/static-build/agent/Dockerfile

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-FROM ubuntu:20.04
+FROM ubuntu:22.04
 ARG RUST_TOOLCHAIN
 
 COPY install_libseccomp.sh /usr/bin/install_libseccomp.sh
@@ -51,6 +51,3 @@ RUN ARCH=$(uname -m); \
 	        *) echo "Unsupported architecture: ${ARCH}" && exit 1 ;; \
     	esac; \
 	rustup target add "${rust_arch}-unknown-linux-${libc}"
-
-# aarch64 requires this name -- link for all
-RUN ln -s /usr/bin/musl-gcc "/usr/bin/$(uname -m)-linux-musl-gcc"