fix warnings during bun run publish-layer

[nangchan]

When running bun run publish-layer the following warnings displayed:

$ bun scripts/publish-layer.ts
101 |     async load() {
102 |         this.type = this.options.type || 'core';
103 |         this.tag = this.options.tag;
104 |         const root = await findRoot(this.options.name, this.options.root);
105 |         if (!root)
106 |             throw new Error(`could not find package.json with ${(0, util_1.inspect)(this.options)}`);
                      ^
warn: could not find package.json with { type: 'dev',

What does this PR do?

Added missing package @oclif/plugin-plugins to resolved warning

• Documentation or TypeScript types (it's okay to leave the rest blank in this case)
• Code changes

How did you verify your code works?

• I ran bun run publish-layer and verified layer was published

[Electroid]

Thanks for fixing this!

[nangchan]

Thanks for fixing this!

Thanks for the merge.