Convert Java8 stream to For loop, since it's not compatible with TC9

TeamCity 9.x using Jersey 1.16, and asm 3.1

ASM 3.1, only supports Java7, so we can't use Java8 streams and such in
the REST API if we want to support TeamCity 9.

It appears that since TC10, Jetbrains have moved to using Jersey 1.19,
and a newer version of ASM which supports Java 8.

This is why this was never seen on TC10 and above. Fixes #156

tcwebhooks-rest-api/src/main/java/webhook/teamcity/server/rest/data/WebHookFinder.java

@@ -1,8 +1,8 @@
 package webhook.teamcity.server.rest.data;
 
+import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Objects;
-import java.util.stream.Collectors;
+import java.util.List;
 
 import org.jetbrains.annotations.NotNull;
 
@@ -82,11 +82,13 @@ private ProjectWebhook getWebHookConfigById(String projectExternalId, final Fiel
 	}
 
 	public Collection<String> getBuildTypeExternalIds(Collection<String> internalIds) {
-		return internalIds.stream()
-				.filter(id ->
-						Objects.nonNull(this.projectManager.findBuildTypeById(id))
-					 && Objects.nonNull(this.projectManager.findBuildTypeById(id).getExternalId()))
-				.map(id -> this.projectManager.findBuildTypeById(id).getExternalId())
-				.collect(Collectors.toList());
+		// Don't use Java8 streams. They don't work with Jersey 1.16 (TC9.x)
+		List<String> externalExternalIds = new ArrayList<>();
+		for (String internalId : internalIds) {
+			if (this.projectManager.findBuildTypeById(internalId) != null) {
+				externalExternalIds.add(this.projectManager.findBuildTypeById(internalId).getExternalId());
+			}
+		}
+		return externalExternalIds;
 	}
 }