perf(actions): only load the files of the used compiler on running build or start commands

[micalevisk]

PR Checklist

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• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

since v10, if we use nodejs v14, we run the build command because of path/posix nodejs package, which is used in the newly added swc compiler integration
Although expected, I found a bit odd that the swc compiler files are loaded even tho we are using tsc/webpack as they are not supposed to be used together

What is the new behavior?

lazily loads few files required for the compiler being used on build and start commands, which decreases the build time a bit

Does this PR introduce a breaking change?

[ ] Yes
[x] No

[kamilmysliwiec]

lgtm