Running ninja with no changes reconfigures meson

Using gst-build git and meson git, also have configured meson to also compile gst-plugins-rs. Every time I rerun ninja, it reconfigures meson.

$ ninja -d explain -n
ninja explain: output build.ninja older than most recent input ../build/subprojects/gst-plugins-rs/libgstrsaudiofx.so (1583938874736613098 vs 1583938876648647571)
[0/1] Regenerating build files.

Taking a second look, looks like all files in build/subprojects/gst-plugins-rs/ are regenerated (or at least their mtime is updated) every time cargo is run without changes.

Reverting 7cf00627 fixes it (thanks to @seungha.yang for bisecting).