fix(integ-runner): disable-update-workflow default is 'false' instead of false (#20073)

`disable-update-workflow` is a boolean, but the default value was a
string 'false'. Update the default to be a boolean `false` value.


----

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Author: corymhall

packages/@aws-cdk/integ-runner/lib/cli.ts

@@ -27,7 +27,7 @@ async function main() {
     .options('max-workers', { type: 'number', desc: 'The max number of workerpool workers to use when running integration tests in parallel', default: 16 })
     .options('exclude', { type: 'boolean', desc: 'All tests should be run, except for the list of tests provided', default: false })
     .options('from-file', { type: 'string', desc: 'Import tests to include or exclude from a file' })
-    .option('disable-update-workflow', { type: 'boolean', default: 'false', desc: 'If this is "true" then the stack update workflow will be disabled' })
+    .option('disable-update-workflow', { type: 'boolean', default: false, desc: 'If this is "true" then the stack update workflow will be disabled' })
     .argv;
 
   const pool = workerpool.pool(path.join(__dirname, '../lib/workers/extract/index.js'), {
@@ -92,7 +92,7 @@ async function main() {
         clean: argv.clean,
         dryRun: argv['dry-run'],
         verbose: argv.verbose,
-        updateWorkflow: !!argv['disable-update-workflow'],
+        updateWorkflow: !argv['disable-update-workflow'],
       });
 
       if (argv.clean === false) {