in_calyptia_fleet: create configuration directory before the fleet header.

[pwhelan]

Summary

Upon first run of the calyptia fleet plugin there will be no fleet directory but the plugin will attempt to create it's base configuration header. Fix that by creating the fleet directory first.

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Testing
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• Example configuration file for the change
• Debug log output from testing the change

• Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• Run local packaging test showing all targets (including any new ones) build.
• Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• Documentation required for this feature

Backporting

• Backport to latest stable release.

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