Markdown code blocks without a type are allowed but can be misinterpreted about arm-learning-paths

[DavidSpickett]

and we put in a fix for the lack of commands for single line blocks

One way is to initialise "ncmd" to 0 here

[DavidSpickett]

Debug output for some of the examples:

```
bash is cool
start: 0x123 size: 345 allocated: true
```

[DEBUG]	Copying command to file .tmpcmd: start: 0x123 size: 345 allocated: true
[DEBUG]	['docker cp .tmpcmd test_0:/home/user/']
[DEBUG]	['docker exec -u user -w /home/user test_0 bash .tmpcmd']
[DEBUG]	Test 1: ERROR (command failed. Return code is 127 but expected 0)

```
cool is bash
start: 0x123 size: 345 allocated: true
```

[INFO]	Parsing content/learning-paths/laptops-and-desktops/dynamic-memory-allocator//2_designing_a_dynamic_memory_allocator.md
[DEBUG]	{'image': ['ubuntu:latest'], 'weight': -1}
[DEBUG]	{'type': 'C', 'ncmd': 2, 0: '#define STORAGE_SIZE 4096', 1: 'static char storage[STORAGE_SIZE];'}
[DEBUG]	{'type': 'bash', 'ret_code': '0', 'ncmd': 1, 0: 'start: 0x123 size: 345 allocated: true'}

So you can see the second line being used as the command.

[DavidSpickett]

And to be clear, if the amount of info comes off as pushy this isn't my intention. I just wanted to give as clear a picture as possible.

I'm also happy to contribute the fixes myself, but being new here, I don't know what direction would be appropriate.