refactor(trie): replace semaphore-async-await with simpler implementation

[faustbrian]

Drops the semaphore-async-await dependency and replaces it with only the bits that we're actually using (which is very little). I left comments with links to the original implementations in the code.

The trie package is now almost free of third-party dependencies, only the readable-stream remains for an unused class. Assuming #2167 gets merged.

[codecov]

Codecov Report

Merging #2187 (cec5757) into master (cec5757) will not change coverage.
The diff coverage is n/a.

❗ Current head cec5757 differs from pull request most recent head 805e92c. Consider uploading reports for the commit 805e92c to get more accurate results

Flag	Coverage Δ
block	93.07% <0.00%> (ø)
blockchain	88.82% <0.00%> (ø)
client	86.67% <0.00%> (ø)
common	98.09% <0.00%> (ø)
devp2p	92.33% <0.00%> (ø)
ethash	∅ <0.00%> (∅)
evm	79.07% <0.00%> (ø)
rlp	∅ <0.00%> (∅)
statemanager	88.71% <0.00%> (ø)
trie	89.29% <0.00%> (ø)
tx	97.98% <0.00%> (ø)
util	93.14% <0.00%> (ø)
vm	85.27% <0.00%> (ø)

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[holgerd77]

Rebased this via UI.

[holgerd77]

Pretty cool, LGTM, just checked, dependency is MIT licensed, so this should be ok. 👍 🙂