fix: Dockerfile warnings

2 warnings found (use --debug to expand):
- FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 1)
- JSONArgsRecommended: JSON arguments recommended for ENTRYPOINT to prevent unintended behavior related to OS signals (line 13)

Dockerfile

@@ -1,4 +1,4 @@
-FROM  devkitpro/devkita64:latest  as  builder
+FROM  devkitpro/devkita64:latest  AS  builder
 
 # install dependencies
 RUN   apt-get  update       \
@@ -10,4 +10,4 @@ RUN   apt-get  update       \
 
 WORKDIR  /app/
 
-ENTRYPOINT  make
+ENTRYPOINT  [ "make" ]