check: give nle_tempochange test more time

These test can take longer than most under valgrind, so give them a
little more time until they timeout.

Part-of: <!160>
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Status Job ID Name Coverage
  Preparation
passed #2496613
gst indent

00:00:13

manual #2496612
manual
manifest
 
  Build
created #2496622
gstreamer
build cerbero cross-android universal
created #2496626
gst-ios-13.2
build cerbero cross-ios universal
created #2496623
gstreamer
build cerbero cross win32
created #2496624
gstreamer
build cerbero cross win64
created #2496621
gstreamer
build cerbero fedora x86_64
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gst-macos-10.15
build cerbero macos x86_64
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build clang fedora x86_64
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docker windows 1809 allowed to fail manual
build msys2
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build nodebug fedora x86_64
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build static fedora x86_64
created #2496616
build static nodebug fedora x86_64
created #2496618
docker windows 1809
build vs2017 amd64
created #2496619
docker windows 1809
build vs2017 x86
 
  Test
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gstreamer
check fedora
created #2496628
gstreamer
integration testsuites fedora 1/4
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gstreamer
integration testsuites fedora 4/4
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gstreamer
valgrind ges
 
  Integrate
created #2496633
cross-android universal examples
created #2496635
gst-ios-13.2
cross-ios universal examples
created #2496634
documentation