Remove assembly in geth-utils (privacy-scaling-explorations#1553)

### Description

Remove geth-utils and examples.

### Type of change

New feature (non-breaking change which adds functionality)

### Rationale

- Assembly was introduced in privacy-scaling-explorations#91 to build examples to use geth-util. It
was not used elsewhere in the codebase.
- The examples are removed as we currently don't use geth-util like the
way the examples show. (Note that the examples also fail to run now. The
transactions in the examples would fail because the trace config
defaults to a 0 block gas limit. It runs after adding a block gas
limit.)
- I found those examples unused when reviewing how we use the tracing
API. It is much easier to review the tracing code after removing the
Assembly.
- The Readme mentioned a TODO CLI, which we never built. I think it
might be interesting to create a good first issue for people to extend
testool(https://github.com/privacy-scaling-explorations/zkevm-circuits/blob/690b2f143a94b7474f0c99493a99b0f2c53d93b8/testool/README.md#L38)
for it.

geth-utils/README.md

@@ -2,19 +2,6 @@
 
 The module `gethutil` tried to provide identical output from APIs `debug_trace*` of latest `geth` as test vectors for [`zkevm-circuits`](https://github.com/privacy-scaling-explorations/zkevm-circuits).
 
-## Usage
-
-<!-- ### CLI Usage -->
-<!-- TODO: Implement a CLI to consume bytecode and output logs -->
-
-### Library Usage
-
-For [`./example/mstore_mload.go`](./example/mstore_mload.go) as an example, it defines bytecode directly by builder `asm`, then write the logs produced by `TraceTx` to stdout. To reproduce the logs, run:
-
-```bash
-go run ./example/mstore_mload.go > ./mstore_mload.json
-```
-
 ### Debugging
 
 The execution traces returned by geth omit some information like execution

geth-utils/build.rs

@@ -26,12 +26,7 @@ fn main() {
     }
 
     // Files the lib depends on that should recompile the lib
-    let dep_files = vec![
-        "./gethutil/asm.go",
-        "./gethutil/trace.go",
-        "./gethutil/util.go",
-        "./go.mod",
-    ];
+    let dep_files = vec!["./gethutil/trace.go", "./go.mod"];
     for file in dep_files {
         println!("cargo:rerun-if-changed={}", file);
     }