Multiple env vars set with ENV need =

As stated in the
[Dockerfile reference](https://docs.docker.com/engine/reference/builder/#env)
In order to set multiple variables at one time you need to use the form
`ENV <key>=<value> ...`

Dockerfile

@@ -7,21 +7,21 @@ RUN apk update && \
 ADD shmig /bin/shmig
 
 ## SHMIG configuration
-ENV TYPE mysql \
-    HOST localhost \
-    PORT 3389 \
-    DATABASE db \
-    LOGIN root \
-    PASSWORD root \
-    ASK_PASSWORD0 0 \
-    MIGRATIONS /sql \
-    MYSQL /usr/bin/mysql \
-    PSQL /usr/bin/psql \
-    SQLITE3 /usr/bin/sqlite3 \
-    UP_MARK "====  UP  ====" \
-    DOWN_MARK "==== DOWN ====" \
-    COLOR auto \
-    SCHEMA_TABLE shmig_version
+ENV TYPE=mysql \
+    HOST=localhost \
+    PORT=3389 \
+    DATABASE=db \
+    LOGIN=root \
+    PASSWORD=root \
+    ASK_PASSWORD=0 \
+    MIGRATIONS=/sql \
+    MYSQL=/usr/bin/mysql \
+    PSQL=/usr/bin/psql \
+    SQLITE3=/usr/bin/sqlite3 \
+    UP_MARK="====  UP  ====" \
+    DOWN_MARK="==== DOWN ====" \
+    COLOR=auto \
+    SCHEMA_TABLE=shmig_version
 
 ADD entrypoint.sh /entrypoint.sh
 ENTRYPOINT ["/entrypoint.sh"]