### Description
Fixes #6934
We weren't verifying that the cookie dir existed before trying to write
the cookie file. This would cause cookie operations to fail if
`.turbo/cookie` got deleted between runs.
e.g.
```
[0 olszewski@chriss-mbp] /tmp/daemon-test $ turbo build --output-logs errors-only
• Packages in scope: @repo/eslint-config, @repo/typescript-config, @repo/ui, docs, web
• Running build in 5 packages
• Remote caching disabled
Tasks: 2 successful, 2 total
Cached: 0 cached, 2 total
Time: 7.847s
[0 olszewski@chriss-mbp] /tmp/daemon-test $ rm -rf .turbo/cookies
[0 olszewski@chriss-mbp] /tmp/daemon-test $ turbo build --output-logs errors-only
• Packages in scope: @repo/eslint-config, @repo/typescript-config, @repo/ui, docs, web
• Running build in 5 packages
• Remote caching disabled
WARNING Failed to check if we can skip restoring outputs for web#build: server is unavailable: failed to write cookie file at /private/tmp/daemon-test/.turbo/cookies/4.cookie: No such file or directory (os error 2). Proceeding to check cache
WARNING Failed to check if we can skip restoring outputs for docs#build: server is unavailable: failed to write cookie file at /private/tmp/daemon-test/.turbo/cookies/5.cookie: No such file or directory (os error 2). Proceeding to check cache
web:build: Failed to mark outputs as cached for web#build: Unavailable("failed to write cookie file at /private/tmp/daemon-test/.turbo/cookies/6.cookie: No such file or directory (os error 2)")
docs:build: Failed to mark outputs as cached for docs#build: Unavailable("failed to write cookie file at /private/tmp/daemon-test/.turbo/cookies/7.cookie: No such file or directory (os error 2)")
Tasks: 2 successful, 2 total
Cached: 2 cached, 2 total
Time: 226ms >>> FULL TURBO
```
### Testing Instructions
Verify that we no longer fail to check if outputs have changed after
deleting the cookies dir:
```
[0 olszewski@chriss-mbp] /tmp/daemon-test $ turbo_dev build --output-logs errors-only
• Packages in scope: @repo/eslint-config, @repo/typescript-config, @repo/ui, docs, web
• Running build in 5 packages
• Remote caching disabled
Tasks: 2 successful, 2 total
Cached: 0 cached, 2 total
Time: 6.968s
[0 olszewski@chriss-mbp] /tmp/daemon-test $ rm -rf .turbo/cookies
[0 olszewski@chriss-mbp] /tmp/daemon-test $ turbo_dev build --output-logs errors-only
• Packages in scope: @repo/eslint-config, @repo/typescript-config, @repo/ui, docs, web
• Running build in 5 packages
• Remote caching disabled
Tasks: 2 successful, 2 total
Cached: 0 cached, 2 total
Time: 6.822s
```
Closes TURBO-2049