Image links are not checked in md files

[marcindulak]

The example below uses docker https://github.com/UmbrellaDocs/linkspector/pull/23

1. build the image of the latest linkspector from source

   git clone https://github.com/UmbrellaDocs/linkspector
   cd linkspector
   docker build --build-arg LINKSPECTOR_PACKAGE= -t umbrelladocs/linkspector .

2. run linkspector check on a test directory

   mkdir test
   cp .gitignore test  # due to https://github.com/UmbrellaDocs/linkspector/issues/24
   echo '![test](test-missing.png "test")' > test/test.md
   docker run --rm -it -v $PWD/test:/app --name linkspector umbrelladocs/linkspector bash -c 'linkspector check'

Output

⠋ Configuration file not found. Using default configuration.
✨ Success: All hyperlinks in the specified files are valid.

An error due to a missing image link is expected.

[marcindulak]

It does not appear to me that this is fixed using https://github.com/UmbrellaDocs/linkspector/commit/c35eb55f29e74bf3161d66e352a21f49e7d4e0f3.

Please use the test instructions provided in the issue description (cp .gitignore test is no longer needed), and reopen the issue if needed.