Router hangs when loading a Parseable but invalid supergraph schema if the telemetry plugin is enabled

[o0Ignition0o]

It turns out loading a super graph that contains validation errors will fail on the Router service builder (as expected). However when the telemetry plugin is enabled the router will hang.

Steps to reproduce:

• Make this change in ./examples/graphql/local.graphql:

diff --git a/examples/graphql/local.graphql b/examples/graphql/local.graphql
index 04295346..969ff1c1 100644
--- a/examples/graphql/local.graphql
+++ b/examples/graphql/local.graphql
@@ -39,7 +39,7 @@ type Product
   inStock: Boolean @join__field(graph: INVENTORY)
   name: String @join__field(graph: PRODUCTS)
   price: Int @join__field(graph: PRODUCTS)
-  reviews: [Review] @join__field(graph: REVIEWS)
+  reviews: [Review] @join__field(graph: PRODUCTS)
   reviewsForAuthor(authorID: ID!): [Review] @join__field(graph: REVIEWS)
   shippingEstimate: Int @join__field(graph: INVENTORY, requires: "price weight")
   upc: String! @join__field(graph: PRODUCTS)

• Run the router with telemetry enabled:

$ cargo r -- -c ./examples/telemetry/otlp.router.yaml -s ./examples/graphql/local.graphql

• Expected: The router fails to start
• Actual: The router hangs, it takes a kill -9 to get the shell back

Notice not providing -c will not set up telemetry and show an error instead such as:

$ cargo r -- -s ./examples/graphql/local.graphql
    Finished dev [unoptimized + debuginfo] target(s) in 0.43s
     Running `target/debug/router -s ./examples/graphql/local.graphql`
2022-04-13T16:26:41.753124Z  INFO apollo_router::executable: apollo-router@0.1.0-preview.4
2022-04-13T16:26:41.805521Z  INFO apollo_router: starting Apollo Router
2022-04-13T16:26:42.475415Z ERROR apollo_router::state_machine: cannot create the router: couldn't build Router Service: query planning had errors: bridge errors: UNKNOWN: Cannot find type Review in subgraph products
2022-04-13T16:26:42.475559Z  INFO apollo_router: stopped with error
2022-04-13T16:26:42.475706Z ERROR apollo_router::executable: could not create the HTTP pipeline: couldn't build Router Service: query planning had errors: bridge errors: UNKNOWN: Cannot find type Review in subgraph products
could not create the HTTP pipeline: couldn't build Router Service: query planning had errors: bridge errors: UNKNOWN: Cannot find type Review in subgraph products