revive llvm builder utility (#154)

Pre-eliminary support for LLVM releases and resolc binary releases by streamlining the build process for all supported hosts platforms.

- Introduce the revive-llvm-builder crate with the revive-llvm builder utilty.
- Do not rely on the LLVM dependency in $PATH to decouple the system LLVM installation from the LLVM host dependency.
- Fix the emscripten build by decoupling the host and native LLVM dependencies. Thus allowing a single LLVM emscripten release that can be used on any host platform.
- An example Dockerfile building an alpine container with a fully statically linked resolc ELF binary.
- Remove the Debian builder utilities and workflow.

crates/llvm-builder/tests/checkout.rs

@@ -0,0 +1,48 @@
+pub mod common;
+
+use std::process::Command;
+
+use assert_cmd::prelude::*;
+
+/// This test verifies that after cloning the LLVM repository, checking out a specific branch
+/// or reference works as expected.
+#[test]
+fn checkout_after_clone() -> anyhow::Result<()> {
+    let test_dir = common::TestDir::with_lockfile(None)?;
+
+    Command::cargo_bin(common::REVIVE_LLVM)?
+        .current_dir(test_dir.path())
+        .arg("clone")
+        .assert()
+        .success();
+
+    Command::cargo_bin(common::REVIVE_LLVM)?
+        .current_dir(test_dir.path())
+        .arg("checkout")
+        .assert()
+        .success();
+
+    Ok(())
+}
+
+/// This test verifies that after cloning the LLVM repository, checking out a specific branch
+/// or reference with the `--force` option works as expected.
+#[test]
+fn force_checkout() -> anyhow::Result<()> {
+    let test_dir = common::TestDir::with_lockfile(None)?;
+
+    Command::cargo_bin(common::REVIVE_LLVM)?
+        .current_dir(test_dir.path())
+        .arg("clone")
+        .assert()
+        .success();
+
+    Command::cargo_bin(common::REVIVE_LLVM)?
+        .current_dir(test_dir.path())
+        .arg("checkout")
+        .arg("--force")
+        .assert()
+        .success();
+
+    Ok(())
+}