add a couple more tests

Author: Jami Cogswell

java/ql/test/query-tests/Telemetry/SupportedExternalApis/SupportedExternalApis.expected

@@ -1,3 +1,9 @@
+| java.net.URL#URL(String) | 2 |
+| java.io.File#File(String) | 1 |
+| java.io.FileWriter#FileWriter(File) | 1 |
 | java.lang.StringBuilder#append(String) | 1 |
 | java.lang.StringBuilder#toString() | 1 |
+| java.net.URL#openConnection() | 1 |
+| java.net.URL#openStream() | 1 |
+| java.net.URLConnection#getInputStream() | 1 |
 | java.util.Map#put(Object,Object) | 1 |

java/ql/test/query-tests/Telemetry/SupportedExternalApis/SupportedExternalApis.java

@@ -1,16 +1,26 @@
 import java.time.Duration;
 import java.util.HashMap;
 import java.util.Map;
+import java.io.InputStream;
+import java.net.URL;
+import java.io.File;
+import java.io.FileWriter;
 
 class SupportedExternalApis {
 	public static void main(String[] args) throws Exception {
-		StringBuilder builder = new StringBuilder();
-		builder.append("foo");  // supported
-		builder.toString();  // supported
+		StringBuilder builder = new StringBuilder(); // uninteresting (parameterless constructor)
+		builder.append("foo");  // supported summary
+		builder.toString();  // supported summary
 
-		Map<String, Object> map = new HashMap<>();
-		map.put("foo", new Object()); // supported
+		Map<String, Object> map = new HashMap<>(); // uninteresting (parameterless constructor)
+		map.put("foo", new Object()); // supported summary
 
 		Duration d = java.time.Duration.ofMillis(1000); // not supported
+
+		URL github = new URL("https://www.github.com/"); // supported summary
+		InputStream stream = github.openConnection().getInputStream(); // supported source (getInputStream), supported sink (openConnection)
+
+		new FileWriter(new File("foo")); // supported sink (FileWriter), supported summary (File)
+		new URL("http://foo").openStream(); // supported sink (openStream), supported summary (URL)
 	}
 }