Fix Homebrew formula to use libexec

See gh-47696

Signed-off-by: Vinicius Lublanski <vlublima@gmail.com>

Author: Lublanski

spring-boot-project/spring-boot-tools/spring-boot-cli/src/main/homebrew/spring-boot.rb

@@ -16,9 +16,14 @@ def install
       root = '.'
     end
 
-    bin.install Dir["#{root}/bin/spring"]
-    lib.install Dir["#{root}/lib/spring-boot-cli-*.jar"]
-    bash_completion.install Dir["#{root}/shell-completion/bash/spring"]
-    zsh_completion.install Dir["#{root}/shell-completion/zsh/_spring"]
+    libexec.install Dir["#{root}/*"]
+    
+	(bin/"spring").write_env_script libexec/"bin/spring", {}
+
+	bash_comp = libexec/"shell-completion/bash/spring"
+	zsh_comp  = libexec/"shell-completion/zsh/_spring"
+
+	bash_completion.install bash_comp if bash_comp.exist?
+	zsh_completion.install  zsh_comp  if zsh_comp.exist?
   end
 end