attrsToString: To avoid some malformed attributes

[arkhamvm]

Error:

TypeError: Cannot convert undefined or null to object
    at Function.keys (<anonymous>)
    at attrsToString

This errors appears if no attrs setted in custom tag:

const BBcodePresetTemp = BbobPresetHTML5.extend((tags: any) => {
	tags.br = () => ({
		tag: 'br',
		// attrs: {}, // <-- Comment this line for error and add [br] to text
		content: null,
	});

	return tags;
});

The dirty fix. Should be test and warning added.

[codecov-io]

Codecov Report

Merging #26 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #26      +/-   ##
==========================================
+ Coverage   93.89%   93.92%   +0.02%     
==========================================
  Files          15       15              
  Lines         475      477       +2     
  Branches      101      102       +1     
==========================================
+ Hits          446      448       +2     
  Misses         23       23              
  Partials        6        6

Impacted Files	Coverage Δ
packages/bbob-plugin-helper/src/index.js	96% <100%> (+0.34%)	⬆️

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[JiLiZART]

Yay! Big thanks to PR!
I think we need some tests to cover this situation :)

[arkhamvm]

I think we need some tests to cover this situation :)

Done.

[JiLiZART]

Thanks! I release patch version soon.