chore: remove SimpleCov code-coverage tooling (#118)

The coverage report was never a gate: `SimpleCov.start` deliberately set no
`minimum_coverage`, nothing in CI read `coverage/`, and no build could fail
because a percentage moved. It cost a development dependency, a require that
had to run before any library code loaded, and a `COVERAGE=false` escape
hatch to work around that ordering constraint.

Drop the gem, the spec_helper block, the gitignored artifact path and the
CONTRIBUTING notes that described it.

YARD documentation coverage (`rake yard:stats`) is unaffected and stays.

Signed-off-by: Tim Smith <tim@mondoo.com>

Author: tas50

.gitignore

@@ -9,7 +9,6 @@ Gemfile.lock
 *.gem
 .bundle
 .config
-coverage
 InstalledFiles
 lib/bundler/man
 pkg

CONTRIBUTING.md

@@ -61,13 +61,8 @@ Useful environment variables:
 | `SEED=12345` | reproduce a specific random ordering |
 | `VERBOSE=1` | print full backtraces on failure |
 | `ONLY_FAILURES=1` | rerun only what failed last time |
-| `COVERAGE=false` | skip SimpleCov |
 | `RSPEC_WARNINGS=true` | enable Ruby warnings |
 
-Coverage is reported to `coverage/` after each run as a diagnostic. **It is not
-a gate** — no build fails because a percentage moved, and neither the coverage
-report nor the documentation build runs in CI.
-
 ## Documentation
 
 The public API is documented with [YARD](https://yardoc.org/):

Gemfile

@@ -9,8 +9,7 @@ end
 
 group :test do
   gem "rake"
-  gem "rspec",     "~> 3.13"
-  gem "simplecov", "~> 0.22"
+  gem "rspec", "~> 3.13"
 end
 
 group :cookstyle do

spec/spec_helper.rb

@@ -6,21 +6,6 @@
 # Licensed under the Apache 2 License.
 # See LICENSE for more details
 
-# Coverage must be started before any library code is loaded, otherwise methods
-# defined at require-time are recorded as uncovered. Set COVERAGE=false to skip
-# it (useful when bisecting or profiling a single spec file).
-unless ENV["COVERAGE"] == "false"
-  require "simplecov"
-
-  SimpleCov.start do
-    enable_coverage :branch
-    add_filter "/spec/"
-    track_files "lib/**/*.rb"
-    # Deliberately no `minimum_coverage`: coverage is a diagnostic here, not a
-    # gate. CI must never fail because a percentage moved.
-  end
-end
-
 require "kitchen"
 require "kitchen/provisioner/dsc"
 require "kitchen-dsc/version"