Remove Rake version constraint for the latest Ruby

Reference: GitHub / ruby / rake / undefined method =~ in Ruby 3.2 mizzy#431 [1]

Error output:

  rake aborted!
  undefined method `=~' for #<Proc:0x00007f488b282050 /opt/hostedtoolcache/Ruby/3.2.2/x64/lib/ruby/gems/3.2.0/gems/rake-10.1.1/lib/rake/application.rb:357 (lambda)>

  (See full trace by running task with --trace)
  Error: Process completed with exit code 1.

[1] ruby/rake#431

specinfra.gemspec

@@ -24,7 +24,7 @@ Gem::Specification.new do |spec|
   spec.add_runtime_dependency "net-telnet" # intentionally version-unspecified for Ruby older than 2.3.0
   spec.add_runtime_dependency "sfl" # required for Ruby older than 1.9.0
 
-  spec.add_development_dependency "rake", "~> 10.1.1"
+  spec.add_development_dependency "rake"
   spec.add_development_dependency "rspec"
   spec.add_development_dependency "rspec-its"
 end