Fix Iroha 2 CI

[nxsaken]

Currently, the I2 PR workflow fails for all jobs. At first glance:

• rust toolchain needs to be updated (to what? should it be synced with iroha?)
• relevant Dockerfile for Python integration tests needs to be located

check

error: failed to compile `cargo-lints v0.1.0`, intermediate artifacts can be found at `/tmp/cargo-install0cVFYh`

Caused by:
  package `eyre v0.6.12` cannot be built because it requires rustc 1.65.0 or newer, while the currently active rustc version is 1.64.0

pytest

error: package `gix-ref v0.38.0` cannot be built because it requires rustc 1.65 or newer, while the currently active rustc version is 1.64.0
💥 maturin failed
  Caused by: Failed to build a native library through cargo
  Caused by: Cargo build finished with "exit status: 101": `env -u CARGO PYO3_ENVIRONMENT_SIGNATURE="cpython-3.7-64bit" PYO3_PYTHON="/usr/bin/python3" PYTHON_SYS_EXECUTABLE="/usr/bin/python3" "cargo" "rustc" "--features" "pyo3/extension-module" "--message-format" "json-render-diagnostics" "--manifest-path" "/__w/iroha-python/iroha-python/Cargo.toml" "--lib"`

integration-test

ERROR: failed to solve: failed to read dockerfile: open /var/lib/docker/tmp/buildkit-mount2907897615/Dockerfile: no such file or directory
Error: buildx failed with: ERROR: failed to solve: failed to read dockerfile: open /var/lib/docker/tmp/buildkit-mount2907897615/Dockerfile: no such file or directory