libftp: add version 0.5.1

[toge]

Specify library name and version: libftp/0.5.1

https://github.com/deniskovalchuk/libftp/compare/v0.5.0...v0.5.1

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• [x] I've read the contributing guidelines.
• [x] I've used a recent Conan client version close to the currently deployed.
• [x] I've tried at least one configuration locally with the conan-center hook activated.

[conan-center-bot]

Conan v1 pipeline :heavy_check_mark:

All green in build 1 (32c9d638f485b2e0efa9784583e3db8b4d8b3d76):

• libftp/0.5.1: All packages built successfully! (All logs)

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Conan v2 pipeline :heavy_check_mark:

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 1 (32c9d638f485b2e0efa9784583e3db8b4d8b3d76):

• libftp/0.5.1: All packages built successfully! (All logs)

[conan-center-bot]

This PR has been automatically merged due to Bump version or Bump dependencies label. Read https://github.com/conan-io/conan-center-index/blob/master/docs/labels.md#bump-version to obtain more information.