SQSCANNER-40 Stop supporting $foo syntax

src/main/java/org/sonarsource/scanner/cli/PropertyResolver.java

@@ -27,7 +27,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 public class PropertyResolver {
-  private static final Pattern placeholderPattern = Pattern.compile("\\$\\{([\\w\\.]+)\\}|\\$([\\w\\.]+)");
+  private static final Pattern placeholderPattern = Pattern.compile("\\$\\{([\\w\\.]+)\\}");
   private final Properties props;
   private final Properties resolved;
   private final List<String> queue;

src/test/java/org/sonarsource/scanner/cli/PropertyResolverTest.java

@@ -104,13 +104,13 @@ public class PropertyResolverTest {
     assertThat(resolved.get("B")).isEqualTo("value b");
     assertThat(resolved.get("C")).isEqualTo("${A value b}");
   }
-  
+
   @Test
   public void missing_var() {
     Map<String, String> env = new HashMap<>();
     Properties map = new Properties();
-    map.put("A", "/path/$missing var/");
-    
+    map.put("A", "/path/${missing} var/");
+
     PropertyResolver resolver = new PropertyResolver(map, env);
     Properties resolved = resolver.resolve();
     assertThat(resolved.get("A")).isEqualTo("/path/ var/");