Motivation

resolves #137

Solution

there is memory leak when using compose which comes from magic-string lib which is a sourcemapping lib.
That lib seems to be not very active, we have opened PR there with the fix, but until that gets picked by maintainers, we need to use that solution as a submod dep.
h-a-n-a/magic-string-rs#27

Checks

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• made this PR as small as possible
• unit-tested any new functionality
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