precompiled: set required_rubygems_version in native gems

Note that we only do this if the platform OS is "linux".

Versions of rubygems before 3.3.22 do not recognize the `-gnu` or
`-musl` suffix on linux platforms. The failure when installing the
gem is

> ERROR:  While executing gem ... (Gem::Exception)
>     Unable to find spec for #<Gem::NameTuple rcee_precompiled, 0.6.test.2024.0128.1724, aarch64-linux>

This PR changes the error message to:

> ERROR:  Error installing rcee_precompiled-0.6.test.2024.0128.1735-x86_64-linux-musl.gem:
> 	rcee_precompiled-0.6.test.2024.0128.1735-x86_64-linux-musl requires RubyGems version >= 3.3.22.
> The current RubyGems version is 3.2.33. Try 'gem update --system' to update RubyGems itself.

Author: flavorjones

precompiled/Rakefile

@@ -42,6 +42,11 @@ Rake::ExtensionTask.new("precompiled", rcee_precompiled_spec) do |ext|
     # remove things not needed for precompiled gems
     spec.dependencies.reject! { |dep| dep.name == "mini_portile2" }
     spec.files.reject! { |file| File.fnmatch?("*.tar.gz", file) }
+
+    if spec.platform.os == "linux"
+      # the `-gnu` suffix is not recognized in earlier versions of rubygems
+      spec.required_rubygems_version.concat([">= 3.3.22"])
+    end
   end
 end