Allow imports from importLocations to import from other import locations (#747)

* Allow imports from importLocations to import from other import locations

* Remove redundant addition of current customImportLocation as schemaLoader.source as all customImportLocations are now added

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Co-authored-by: erlend <erlend@scelto.no>

Author: erlendnils1

schema2proto-lib/src/main/java/no/entur/schema2proto/generateproto/ProtoSerializer.java

@@ -432,7 +432,9 @@ private List<String> getFullyQualifiedTypes(String pathName) {
 					File fileToImport = new File(path, pathName);
 					if (fileToImport.exists()) {
 						SchemaLoader schemaLoader = new SchemaLoader();
-						schemaLoader.addSource(path);
+						for (String importRootFolder : configuration.customImportLocations) {
+							schemaLoader.addSource(new File(importRootFolder).toPath());
+						}
 						schemaLoader.addProto(pathName);
 						Schema schema = schemaLoader.load();
 						ProtoFile customImportFile = schema.protoFile(pathName);