fix: resolve plugins from npm packages correctly

[volodymyr-rutskyi]

What/Why/How?

When the CLI is installed globally and tries to resolve a plugin from NPM package, it can't find it because by default the require.resolve tries to look for the package from the CLI installation location. This would cause errors like below even though the plugin package is installed in the project's node_modules directory:

Something went wrong when processing :

  - Failed to load plugin "@redocly/portal-plugin-async-api/plugin.js": Cannot find module '@redocly/portal-plugin-async-api/plugin.js'

Added the config directory as an additional path to look for NPM packages when resolving plugins.

Reference

Reported in internal conversation

Testing

Screenshots (optional)

Check yourself

• Code changed? - Tested with redoc/reference-docs/workflows (internal)
• All new/updated code is covered with tests
• New package installed? - Tested in different environments (browser/node)

Security

• Security impact of change has been considered
• Code follows company security practices and guidelines

[changeset-bot]

🦋 Changeset detected

Latest commit: 8c43dd2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@redocly/openapi-core	Patch
@redocly/cli	Patch

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[github-actions]

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
redocly lint packages/core/src/benchmark/benches/rebilly.yaml	994.5 ± 13.2	963.3	1012.8	1.00
redocly-next lint packages/core/src/benchmark/benches/rebilly.yaml	998.2 ± 26.6	955.8	1055.4	1.00 ± 0.03

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	78.56%	4993/6356
🟡	Branches	67.19%	2062/3069
🟡	Functions	72.98%	824/1129
🟡	Lines	78.85%	4711/5975

Test suite run success

809 tests passing in 121 suites.

Report generated by 🧪jest coverage report action from 8c43dd2

[tatomyr]

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