Function To Add entry to known_gaps

This commit contains all the code needed to update the `known_gaps` table. It uses a generic function `PushKnownGaps` to insert gaps to the database.

The current test is very "basic." All it does it insert a dummy gap into the database. As long as their is no error it will return succesfully.

I have also removed the foundry subfolder. I am using the `related-repository` setup for testing.

Author: Abdul Rabbani

.gitignore

@@ -49,3 +49,8 @@ profile.cov
 **/yarn-error.log
 foundry/deployments/local-private-network/geth-linux-amd64
 foundry/projects/local-private-network/geth-linux-amd64
+
+# Helpful repos
+related-repositories/foundry-test/**
+related-repositories/hive/**
+related-repositories/ipld-eth-db/**

.gitmodules

@@ -5,7 +5,4 @@
 [submodule "evm-benchmarks"]
 	path = tests/evm-benchmarks
 	url = https://github.com/ipsilon/evm-benchmarks
-	shallow = true
-[submodule "foundry/projects/local-private-network/Stateful/lib/ds-test"]
-	path = foundry/projects/local-private-network/Stateful/lib/ds-test
-	url = https://github.com/dapphub/ds-test
+	shallow = true