Fixed warnings

Author: sbuliarca

Dockerfile

@@ -1,10 +1,10 @@
-FROM alpine:3.22 as tmp
+FROM alpine:3.22 AS tmp
 
 RUN --mount=type=cache,target=/var/cache/apk \
     apk add curl
 
-ENV VERSION 1.0.1
-ENV JAR jmx_prometheus_javaagent-$VERSION.jar
+ENV VERSION=1.0.1
+ENV JAR=jmx_prometheus_javaagent-$VERSION.jar
 
 RUN curl -L https://repo1.maven.org/maven2/io/prometheus/jmx/jmx_prometheus_javaagent/$VERSION/$JAR -o /lib/$JAR