fix(issuance): remove redundant compilation from test build script

The build:dep step already compiles @graphprotocol/issuance as a dependency,
so the explicit --filter @graphprotocol/issuance compile in build:self was
redundant and inefficient.

Now follows the same pattern as packages/contracts/test which only builds
dependencies without redundant compilation steps.

Author: RembrandtK

packages/issuance/test/package.json

@@ -45,7 +45,7 @@
   "scripts": {
     "build": "pnpm build:dep && pnpm build:self",
     "build:dep": "pnpm --filter '@graphprotocol/issuance-test^...' run build:self",
-    "build:self": "tsc --build && pnpm --filter @graphprotocol/issuance compile && pnpm generate:interfaces",
+    "build:self": "tsc --build && pnpm generate:interfaces",
     "generate:interfaces": "node scripts/generateInterfaceIds.js --silent",
     "clean": "rm -rf build",
     "test": "pnpm build && pnpm test:self",