Ports: Avoid absolute paths for install(1)

Just because your distro installs install(1) to /usr/bin doesn't mean
every distro does.

Ports/alpine/package.sh

@@ -39,8 +39,7 @@ install() {
     run make DESTDIR="$DESTDIR" "${installopts[@]}" install
     # Install system configuration file that tells Alpine where to find CA certificates
     # installed from the `ca-certificates` package.
-    # (The full `/usr/bin/install` path is used because `install()` is a function within this script.)
-    run /usr/bin/install \
+    run command install \
         --mode=644 \
         --no-target-directory \
         -D \

Ports/tree-sitter-vim/package.sh

@@ -12,5 +12,5 @@ build() {
 }
 
 install() {
-    run /usr/bin/install -m755 libtree-sitter-vim.so "${SERENITY_INSTALL_ROOT}/usr/local/lib/libtree-sitter-vim.so"
+    run command install -m755 libtree-sitter-vim.so "${SERENITY_INSTALL_ROOT}/usr/local/lib/libtree-sitter-vim.so"
 }