fix: migrate entry injection to hooks

[rishabh3112]

• This is a bugfix
• This is a feature
• This is a code refactor
• This is a test update
• This is a docs update
• This is a metadata update

For Bugs and Features; did you add new tests?

Shouldn't require change

Motivation / Use-Case

/cc @alexander-akait
Helps fixing #3351

Breaking Changes

No

Additional Info

No

[snitin315]

Need to rebase.

[codecov]

Codecov Report

Merging #3424 (30eaf1b) into master (2b53b00) will decrease coverage by 2.38%.
The diff coverage is 81.56%.

❗ Current head 30eaf1b differs from pull request most recent head e1daeff. Consider uploading reports for the commit e1daeff to get more accurate results

@@            Coverage Diff             @@
##           master    #3424      +/-   ##
==========================================
- Coverage   95.24%   92.86%   -2.39%     
==========================================
  Files          34       33       -1     
  Lines        1326     1317       -9     
  Branches      392      405      +13     
==========================================
- Hits         1263     1223      -40     
- Misses         59       85      +26     
- Partials        4        9       +5     

Impacted Files	Coverage Δ
bin/cli-flags.js	100.00% <ø> (ø)
client-src/index.js	83.18% <57.14%> (-7.89%)	⬇️
lib/utils/findCacheDir.js	61.90% <61.90%> (ø)
lib/utils/DevServerPlugin.js	84.39% <74.66%> (-12.80%)	⬇️
lib/servers/SockJSServer.js	90.69% <77.77%> (-4.04%)	⬇️
lib/Server.js	95.23% <97.77%> (+0.21%)	⬆️
client-src/clients/SockJSClient.js	100.00% <100.00%> (ø)
client-src/clients/WebsocketClient.js	100.00% <100.00%> (+11.76%)	⬆️
lib/servers/WebsocketServer.js	97.36% <100.00%> (+0.30%)	⬆️
lib/utils/getCertificate.js	88.46% <100.00%> (ø)
... and 6 more

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[rishabh3112]

Need review 😃

[alexander-akait]

Avoid using this, webpack should public export this

[rishabh3112]

Should I send PR to webpack then?

[rishabh3112]

@alexander-akait 😅

[ylemkimon]

Note this is no longer needed as of #3467.

[rishabh3112]

Closing this PR.
@alexander-akait if this is needed, let me know. I would start fresh.