fast_float: add version 3.9.0, remove older versions

[toge]

Specify library name and version: fast_float/*

• add version 3.9.0
• remove older versions
• use add_subdirectory in test_v1_package

---

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

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 2 (dd37e3e069c0abcc158b81f8ac49a199a7ea6c9d):

• fast_float/3.8.0@:
  All packages built successfully! (All logs)

• fast_float/3.6.0@:
  All packages built successfully! (All logs)

• fast_float/3.8.1@:
  All packages built successfully! (All logs)

• fast_float/3.7.0@:
  All packages built successfully! (All logs)

• fast_float/1.1.2@:
  All packages built successfully! (All logs)

• fast_float/3.4.0@:
  All packages built successfully! (All logs)

• fast_float/0.9.0@:
  All packages built successfully! (All logs)

• fast_float/2.0.0@:
  All packages built successfully! (All logs)

• fast_float/3.5.1@:
  All packages built successfully! (All logs)

• fast_float/3.9.0@:
  All packages built successfully! (All logs)