Fix path to importer-csv in .travis.yml.

Author: clems4ever

.travis.yml

@@ -7,4 +7,4 @@ script:
 - go test -v ./...
 - pushd web && npm ci && npm run build && popd
 - go build -o go-graphkb cmd/go-graphkb/main.go
-- go build -o source-csv cmd/source-csv/main.go
+- go build -o importer-csv cmd/importer-csv/main.go