Add Ethereum block tag para-test (#1831)

* Add Ethereum block tag para-test

* unskip

tests/para-tests/moonbase/test-eth-rpc-block-tags.ts

@@ -0,0 +1,31 @@
+import { expect } from "chai";
+import { ALITH_ADDRESS, ALITH_GENESIS_TRANSFERABLE_BALANCE } from "../../util/accounts";
+
+import { describeParachain } from "../../util/setup-para-tests";
+
+describeParachain(
+  "Ethereum RPC block tags",
+  {
+    parachain: {
+      chain: "moonbase-local",
+    },
+  },
+  (context) => {
+    it("should support pending tag", async function () {
+      this.timeout(150000);
+      await context.waitBlocks(1);
+      const expectedBalance = await context.web3.eth.getBalance(ALITH_ADDRESS, "pending");
+      expect(BigInt(expectedBalance)).to.equal(ALITH_GENESIS_TRANSFERABLE_BALANCE);
+    });
+    it("should support merge tags in the parachain context", async function () {
+      this.timeout(150000);
+      await context.waitBlocks(3);
+      // We waited for 3 more blocks, expect best block to be number 4.
+      expect((await context.web3.eth.getBlock("latest")).number).to.equal(4);
+      // `finalized` block to be 2.
+      expect((await context.web3.eth.getBlock("finalized")).number).to.equal(2);
+      // `safe` block to be an alias of `finalized` in the Polkadot context.
+      expect((await context.web3.eth.getBlock("safe")).number).to.equal(2);
+    });
+  }
+);