CI: Install wget package for Alpine Linux

Recently, we have been transitioning from using curl to wget for
downloading files from remote hosts. However, the version of wget
provided by Alpine Linux is actually a Busybox implementation, which
lacks many features found in the full wget package.

Error messages:
  sysprog21#15 [linux/amd64 base_gcc 5/6] RUN make ENABLE_SDL=0
  sysprog21#15 0.207 Check the file build/.config for configured items.
  sysprog21#15 0.360 Fetching prebuilt executables from "rv32emu-prebuilt" ...
  sysprog21#15 0.361 wget: unrecognized option: show-progress

This commit attempts to install wget package instead.

Author: jserv

Dockerfile

@@ -1,6 +1,6 @@
 FROM alpine:3.19 as base_gcc
 
-RUN apk add --update alpine-sdk git curl
+RUN apk add --update alpine-sdk git wget
 
 # copy in the source code
 WORKDIR /home/root/rv32emu