update message about finding a single application to run the tests

Author: aminya

script/test

@@ -49,15 +49,15 @@ const resourcePath = CONFIG.repositoryRootPath
 let executablePath
 if (process.platform === 'darwin') {
   const executablePaths = glob.sync(path.join(CONFIG.buildOutputPath, '*.app'))
-  assert(executablePaths.length === 1, `More than one application to run tests against was found. ${executablePaths.join(',')}`)
+  assert(executablePaths.length === 1, `A single application to run tests against was not found. ${executablePaths.join(',')}`)
   executablePath = path.join(executablePaths[0], 'Contents', 'MacOS', path.basename(executablePaths[0], '.app'))
 } else if (process.platform === 'linux') {
   const executablePaths = glob.sync(path.join(CONFIG.buildOutputPath, 'atom-*', 'atom'))
-  assert(executablePaths.length === 1, `More than one application to run tests against was found. ${executablePaths.join(',')}`)
+  assert(executablePaths.length === 1, `A single application to run tests against was not found. ${executablePaths.join(',')}`)
   executablePath = executablePaths[0]
 } else if (process.platform === 'win32') {
   const executablePaths = glob.sync(path.join(CONFIG.buildOutputPath, '**', 'atom*.exe'))
-  assert(executablePaths.length === 1, `More than one application to run tests against was found. ${executablePaths.join(',')}`)
+  assert(executablePaths.length === 1, `A single application to run tests against was not found. ${executablePaths.join(',')}`)
   executablePath = executablePaths[0]
 } else {
   throw new Error('##[error] Running tests on this platform is not supported.')