[build] Remove unnecessary entries in the Dockerfile.

Cmake isn't used in the build script and make is installed on
the container image using apk and doesn't need to be compiled from
source.

.github/actions/muslbuilder/Dockerfile

@@ -10,7 +10,6 @@ RUN apk update && apk add --no-cache \
     binutils \
     m4 \
     git \
-    cmake \
     make \
     libgcc \
     musl-dev \
@@ -38,7 +37,6 @@ RUN apk update && apk add --no-cache \
     linux-headers
 
 ADD https://www.libarchive.org/downloads/libarchive-3.6.2.tar.gz /
-ADD https://ftp.gnu.org/gnu/make/make-4.2.1.tar.gz /
 ADD https://ftp.gnu.org/gnu/ncurses/ncurses-6.4.tar.gz /
 ADD https://github.com/PCRE2Project/pcre2/releases/download/pcre2-10.42/pcre2-10.42.tar.gz /
 ADD https://ftp.gnu.org/gnu/readline/readline-6.3.tar.gz /
@@ -108,7 +106,6 @@ RUN cd /extract/libarchive-* && \
  make -j2 && \
  make install && make clean
 
-RUN cd /extract/make-4.2.1 && ./configure --prefix=/fake.root && make -j2 && make install && make clean
 RUN cd /extract/readline-* && ./configure --prefix=/fake.root && make -j2 && make install && make clean
 
 RUN cd /extract/sqlite-* && \