Bump libpng's zlib requirement to [>=1.2.11 <2] range

[AbrilRBS]

Specify library name and version: lib/1.0

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[github-actions]

🤖 Beep Boop! This pull request is making changes to 'recipes/libpng//'.

👋 @Hopobcn you might be interested. 😉

[ghost]

I detected other pull requests that are modifying libpng/all recipe:

• libpng: add with_zlibng option #18280

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 1 (ddc6f0051ce1ed46e2106529875c2e235f92885a):

• libpng/1.6.38:
  All packages built successfully! (All logs)

• libpng/1.6.39:
  All packages built successfully! (All logs)

• libpng/1.6.40:
  All packages built successfully! (All logs)

• libpng/1.6.32:
  All packages built successfully! (All logs)

• libpng/1.5.30:
  All packages built successfully! (All logs)

• libpng/1.6.37:
  All packages built successfully! (All logs)

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Conan v2 pipeline ✔️

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All green in build 1 (ddc6f0051ce1ed46e2106529875c2e235f92885a):

• libpng/1.6.37:
  All packages built successfully! (All logs)

• libpng/1.6.32:
  All packages built successfully! (All logs)

• libpng/1.6.40:
  All packages built successfully! (All logs)

• libpng/1.6.39:
  All packages built successfully! (All logs)

• libpng/1.5.30:
  All packages built successfully! (All logs)

• libpng/1.6.38:
  All packages built successfully! (All logs)