CI: Update to Fedora 40

Replace !5525 (closed) so that the repo/branch naming doesn't make windows sad

Needs:

• !5432 (merged)
• GIR file have new fields and must be updated
• clang warning in vulkan video code !5996 (merged)
• Fluster crash
  • Disabled for now, requires someone to look at why it crashes
• Documentation build issues
  • Missing core glib symbols from upstream devhelp
  • Add symbols (for plugins which are dynamically generated or were previously not built on CI) to symbol list
  • codecparser symbol failure : #3822 (closed)
• Failing unit tests
  • gst-plugins-bad.elements_dash_mpd.dash_mpdparser_xlink_period
  • gst-plugins-bad.elements_netsim.netsim_stress_delayed race ? #792
  • validate.dash.playback.reverse_playback.dash_exMPD_BIP_TC1 #3733
  • gst-plugins-good.elements_mpegaudioparse.test_parse_gapless_and_skip_padding_samples race ?
  • gst-plugins-bad.validate.autovideoconvert.renegotiate race ?
• Add missing OpenSSL valgrind supressions (see https://stackoverflow.com/questions/21532371/memory-leak-in-openssl-function-evp-pkey-keygen)
• Valgrind failures
  • lc3 !7657 (merged)
• Re-enable GST_WERROR: "true"