cpp-httplib: conan v2 support

[SpaceIm]

Specify library name and version: lib/1.0

This is also a good place to share with all of us why you are submitting this PR (specially if it is a new addition to ConanCenter): is it a dependency of other libraries you want to package? Are you the author of the library? Thanks!

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• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the conan-center hook activated.

[conan-center-bot]

All green in build 1 (e4f2e29b7b3903f416bb73d83d8ff1f4fb16236f):

• cpp-httplib/0.10.8@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.9@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.7@:
  All packages built successfully! (All logs)

• cpp-httplib/0.11.0@:
  All packages built successfully! (All logs)

• cpp-httplib/0.11.1@:
  All packages built successfully! (All logs)

• cpp-httplib/0.8.9@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.4@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.3@:
  All packages built successfully! (All logs)

• cpp-httplib/0.9.10@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.6@:
  All packages built successfully! (All logs)

• cpp-httplib/0.7.18@:
  All packages built successfully! (All logs)

• cpp-httplib/0.6.6@:
  All packages built successfully! (All logs)

• cpp-httplib/0.5.13@:
  All packages built successfully! (All logs)

• cpp-httplib/0.10.1@:
  All packages built successfully! (All logs)