squeezer: Support animation disablement

This will animate the child transitions only if animations are enabled.

Fixes #140.
8 jobs for master in 10 minutes and 11 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #124900
librem5
build-debian-clang

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passed #124898
librem5
build-debian-gcc

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passed #124899
librem5
build-debian-gcc-static

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passed #124901
librem5
build-fedora-gcc

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  Docs
passed #124902
librem5
build-gtkdoc

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  Test
passed #124903
librem5
unit-test

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41.5%
 
  Package
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librem5
package-debian

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  Deploy
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librem5
publish-docs

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