feat: add unit tests with --release flag

Rust does optimizations which can cause havoc
in `--release` mode, so add another set of unit tests
with all optimizations enabled.

Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>

.buildkite/test_description.json

@@ -44,6 +44,29 @@
         "privileged": true
       }
     },
+    {
+      "test_name": "unittests-gnu-release",
+      "command": "cargo test --release --all-features --workspace",
+      "platform": [
+        "x86_64",
+        "aarch64",
+        "riscv64"
+      ],
+      "docker_plugin": {
+        "privileged": true
+      }
+    },
+    {
+      "test_name": "unittests-musl-release",
+      "command": "cargo test --release --all-features --workspace --target {target_platform}-unknown-linux-musl",
+      "platform": [
+        "x86_64",
+        "aarch64"
+      ],
+      "docker_plugin": {
+        "privileged": true
+      }
+    },
     {
       "test_name": "clippy",
       "command": "cargo clippy --workspace --bins --examples --benches --all-features --all-targets -- -D warnings -D clippy::undocumented_unsafe_blocks",