feat: switch to posix version

Author: Hweinstock

server/aws-lsp-codewhisperer/src/language-server/agenticChat/tools/executeBash.test.ts

@@ -2,10 +2,8 @@ import { strict as assert } from 'assert'
 import * as mockfs from 'mock-fs'
 import * as sinon from 'sinon'
 import { ExecuteBash } from './executeBash'
-import { processUtils } from '@aws/lsp-core'
 import { Logging } from '@aws/language-server-runtimes/server-interface'
 import { TestFeatures } from '@aws/language-server-runtimes/testing'
-import { Writable } from 'stream'
 
 describe('ExecuteBash Tool', () => {
     let logging: Logging

server/aws-lsp-codewhisperer/src/language-server/agenticChat/tools/executeBash.ts

@@ -305,7 +305,8 @@ export class ExecuteBash {
     }
 
     private static async whichCommand(logger: Logging, cmd: string): Promise<string> {
-        const cp = new processUtils.ChildProcess(logger, 'which', [cmd], {
+        // use 'command -v' instead as which isn't POSIX
+        const cp = new processUtils.ChildProcess(logger, 'command', ['-v', cmd], {
             collect: true,
             waitForStreams: true,
         })