BGL Weak Pointer Deduplication Pool (#4927)

* Ho boy

* BGL pool finished

* Remove id32 feature

* Add BGL Test

* Iteration

* Working Dedupe

* Tests

* Iteration

* Re-iteration

* Hash Cleanup

* Add large slew of tests

* Whoops

Author: cwfitzgerald

.config/nextest.toml

@@ -0,0 +1,4 @@
+# Use two threads for tests with "2_threads" in their name
+[[profile.default.overrides]]
+filter = 'test(~2_threads)'
+threads-required = 2