refactor: remove lua md5 dependency

Dockerfile

@@ -21,7 +21,6 @@ RUN luarocks install --lua-version=5.4 luasocket && \
     luarocks install --lua-version=5.4 luasec && \
     luarocks install --lua-version=5.4 luaposix && \
     luarocks install --lua-version=5.4 lpeg && \
-    luarocks install --lua-version=5.4 md5 && \
     luarocks install --lua-version=5.4 dkjson && \
     luarocks install --lua-version=5.4 luacheck && \
     cargo install stylua@0.18.1 --features lua54

README.md

@@ -45,7 +45,6 @@ sudo luarocks install --lua-version=5.4 dkjson
 sudo luarocks install --lua-version=5.4 luasocket
 sudo luarocks install --lua-version=5.4 luasec
 sudo luarocks install --lua-version=5.4 luaposix
-sudo luarocks install --lua-version=5.4 md5
 ```
 #### MacOS
 
@@ -58,7 +57,6 @@ sudo luarocks install --lua-version=5.4 dkjson
 sudo luarocks install --lua-version=5.4 luasocket
 sudo luarocks install --lua-version=5.4 luasec
 sudo luarocks install --lua-version=5.4 luaposix
-sudo luarocks install --lua-version=5.4 md5
 ```
 
 ##### Homebrew
@@ -69,7 +67,6 @@ luarocks --lua-dir=$(brew --prefix)/opt/lua@5.4 install dkjson
 luarocks --lua-dir=$(brew --prefix)/opt/lua@5.4 install luasocket
 luarocks --lua-dir=$(brew --prefix)/opt/lua@5.4 install luasec
 luarocks --lua-dir=$(brew --prefix)/opt/lua@5.4 install luaposix
-luarocks --lua-dir=$(brew --prefix)/opt/lua@5.4 install md5
 ```
 
 For emulator scripts to work it is expected that `lua5.4` binary is available in the system PATH. If operating system/package manager that you are using provides only `lua` or lua binary named in a different way (e.g. on `Homebrew`), please create symbolic link or alias `lua5.4`.

src/tests/machine-test.lua

@@ -18,7 +18,6 @@
 
 local cartesi = require("cartesi")
 local test_util = require("tests.util")
-local md5 = require("md5")
 
 -- Note: for grpc machine test to work, remote-cartesi-machine must run on
 -- same computer and remote-cartesi-machine execution path must be provided