boost: Remove version 1.70.0 to reduce the size of the recipe folder

[jwillikers]

This is necessary for adding Boost version 1.82.0 in PR #17471.

Specify library name and version: boost/1.70.0

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• 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.

[github-actions]

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

👋 @grafikrobot @Hopobcn @jwillikers you might be interested. 😉

[ghost]

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

• (#17515) [boost]: patch for boost::log #17516
• Add Boost 1.82.0 #17471
• Boost Conan 2.0 compatibility #16222

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

[SpaceIm]

This hook may be relaxed for boost.

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 3 (5dc306e2071a52d59f29d3224fd1ab380a99c27b):

• boost/1.78.0@:
  All packages built successfully! (All logs)

• boost/1.80.0@:
  All packages built successfully! (All logs)

• boost/1.81.0@:
  All packages built successfully! (All logs)

• boost/1.79.0@:
  All packages built successfully! (All logs)

• boost/1.76.0@:
  All packages built successfully! (All logs)

• boost/1.74.0@:
  All packages built successfully! (All logs)

• boost/1.75.0@:
  All packages built successfully! (All logs)

• boost/1.73.0@:
  All packages built successfully! (All logs)

• boost/1.72.0@:
  All packages built successfully! (All logs)

• boost/1.71.0@:
  All packages built successfully! (All logs)

• boost/1.77.0@:
  All packages built successfully! (All logs)

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Conan v2 pipeline ✔️

Note: Conan v2 builds may be required once they are on the v2 ready list

All green in build 2 (5dc306e2071a52d59f29d3224fd1ab380a99c27b):

• boost/1.80.0@:
  All packages built successfully! (All logs)

• boost/1.75.0@:
  All packages built successfully! (All logs)

• boost/1.72.0@:
  All packages built successfully! (All logs)

• boost/1.78.0@:
  All packages built successfully! (All logs)

• boost/1.74.0@:
  All packages built successfully! (All logs)

• boost/1.79.0@:
  All packages built successfully! (All logs)

• boost/1.81.0@:
  All packages built successfully! (All logs)

• boost/1.73.0@:
  All packages built successfully! (All logs)

• boost/1.77.0@:
  All packages built successfully! (All logs)

• boost/1.71.0@:
  All packages built successfully! (All logs)

• boost/1.76.0@:
  All packages built successfully! (All logs)

[AbrilRBS]

This feels "better" for me as it reduces CI load when building Boost 😛