chore(cli): set termination-protection to false by default (aws#9096)

Following up on: https://github.com/aws/aws-cdk/pull/9058/files

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packages/aws-cdk/bin/cdk.ts

@@ -76,7 +76,7 @@ async function parseCommandLineArguments() {
       .option('trust', { type: 'array', desc: 'The AWS account IDs that should be trusted to perform deployments into this environment (may be repeated)', default: [], nargs: 1, requiresArg: true, hidden: true })
       .option('cloudformation-execution-policies', { type: 'array', desc: 'The Managed Policy ARNs that should be attached to the role performing deployments into this environment. Required if --trust was passed (may be repeated)', default: [], nargs: 1, requiresArg: true, hidden: true })
       .option('force', { alias: 'f', type: 'boolean', desc: 'Always bootstrap even if it would downgrade template version', default: false })
-      .option('termination-protection', { type: 'boolean', default: true, desc: 'Toggle CloudFormation termination protection on the bootstrap stacks' }),
+      .option('termination-protection', { type: 'boolean', default: false, desc: 'Toggle CloudFormation termination protection on the bootstrap stacks' }),
     )
     .command('deploy [STACKS..]', 'Deploys the stack(s) named STACKS into your AWS account', yargs => yargs
       .option('build-exclude', { type: 'array', alias: 'E', nargs: 1, desc: 'Do not rebuild asset with the given ID. Can be specified multiple times.', default: [] })