fix: parsing of stack trace for bun runtime

[nazarhussain]

Description

Fixes the different parsing logic for the bun runtime that is affecting the mocking.

Resolves #9031

Here is stack trace for the NodeJS runtime.

'Error: $$stack trace error',
'    at createSimpleStackTrace (file:///my-project/node_modules/@vitest/utils/dist/helpers.js:43:14)',
'    at getImporter (file:///my-project/node_modules/vitest/dist/chunks/vi.BZvkKVkM.js:3769:21)',
'    at Object.mock (file:///my-project/node_modules/vitest/dist/chunks/vi.BZvkKVkM.js:3655:21)',
'    at /my-project/packages/beacon-node/test/unit/api/impl/events/events.test.ts:2:26',
'    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)'

Here is stack trace for the Bun runtime for same scenario.

'Error: $$stack trace error',
'    at createSimpleStackTrace (/my-project/node_modules/@vitest/utils/dist/helpers.js:43:18)',
'    at getImporter (/my-project//node_modules/vitest/dist/chunks/vi.BZvkKVkM.js:3754:21)',
'    at mock (/my-project/node_modules/vitest/dist/chunks/vi.BZvkKVkM.js:3655:21)',
'    at <anonymous> (/my-project/packages/beacon-node/test/unit/api/impl/events/events.test.ts:2:30)',
'    at runInlinedModule (/my-project/node_modules/vitest/dist/module-evaluator.js:136:118)',
'    at directRequest (/my-project/node_modules/vitest/node_modules/vite/dist/node/module-runner.js:1112:80)',
'    at cachedRequest (/my-project/node_modules/vitest/node_modules/vite/dist/node/module-runner.js:1030:79)',
'    at processTicksAndRejections (native)'

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