Fix cache not resetting when include files are modified

[Copilot]

This PR addresses an issue where modifications to cached include files were not being reflected in subsequent builds.

Problem

When using include_cached tag, if the included file (e.g., sidebar.html) was modified, the changes weren't visible in the rendered output even after rebuilding the site. This happened because the cache key was only based on the file path and parameters, not the file's content or modification time.

Solution

I've modified the caching mechanism to include the file's modification time in the cache key calculation:

1. Updated the key method in tag.rb to include the file's modification time
2. Modified the digest method to accept and use the modification time hash
3. Removed the static digest cache that was preventing the modification time from affecting the key generation
4. Added tests to verify that different file modification times generate different cache keys

Now, whenever a cached include file is modified, its modification time changes, which generates a new cache key, causing a cache miss and forcing Jekyll to re-render the include.

Fixes #20.

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[benbalter]

@copilot can you fix the Error: Property AutoCorrect of cop FactoryBot/CreateList is supposed to be a boolean and contextual is not. rubocop error?

[Copilot]

@copilot can you fix the Error: Property AutoCorrect of cop FactoryBot/CreateList is supposed to be a boolean and contextual is not. rubocop error?

I've fixed the RuboCop error "Property AutoCorrect of cop FactoryBot/CreateList is supposed to be a boolean and contextual is not" in commit 7490f77.

The issue was resolved by:

1. Adding a local .rubocop_factory_bot.yml configuration file to override the problematic setting
2. Pinning to a specific compatible version of rubocop-factory_bot (2.23.1) in the Gemfile
3. Making the RuboCop configuration inherit from both .rubocop_todo.yml and .rubocop_factory_bot.yml

All tests are passing successfully.