improve some ci scripts

.ci/exec-macos-platform.sh

@@ -14,7 +14,7 @@ export IRRLICHT_LIB_DIR=$PWD/irrlicht/lib/$(arch)
 ./premake5 gmake --cc=clang --build-freetype --build-sqlite
 
 cd build
-make config=release -j4
+make config=release -j$(nproc)
 cd ..
 
 mkdir ygopro-platforms

.ci/libevent-prebuild.sh

-#!/bin/bash
+#!/bin/sh
 set -x
 set -o errexit
 # PROCESSOR_COUNT=4
 
-wget -O - https://cdn01.moecube.com/ygopro-build-materials/libevent-2.0.22-stable.tar.gz | tar zfx -
+if [ -d "libevent-stable" ]; then
+  rm -rf libevent-stable
+fi
+
+if [ ! -d "libevent-2.0.22-stable" ]; then
+  wget -O - https://cdn01.moecube.com/ygopro-build-materials/libevent-2.0.22-stable.tar.gz | tar zfx -
+fi
+
+install_path="$PWD/libevent-stable"
+
 cd libevent-2.0.22-stable
-./configure --prefix=$PWD/libevent-stable --disable-openssl --enable-static=yes --enable-shared=no
-make -j$PROCESSOR_COUNT
+./configure "--prefix=$install_path" --disable-openssl --enable-static=yes --enable-shared=no
+make -j$(nproc)
 make install
 cd ..
-mv libevent-2.0.22-stable/libevent-stable .
-rm -rf libevent-2.0.22-stable