ucode: update to latest Git HEAD

ucode: update to latest Git HEAD

46d93c9 tests: fixup testcases
4c654df types: adjust double printing format
eac2add compiler: fix bytecode for logical assignments of properties
3903b18 fs: add `realpath()` function
8366102 math: add isnan() function
eef83d3 tests: relax sleep() test
394e901 lib: uc_json(): accept trailing whitespace when parsing strings
1867c8b uloop: terminate parent uloop in task child processes
d2cc003 uci: auto-load package in `ctx.foreach()` and `ctx.get_first()`
6c5ee53 compiler: ensure that arrow functions with block bodies return no value
fdc9b6a compiler: fix `??=`, `||=` and `&&=` logical assignment semantics
88dcca7 add cmake to install requires for debian

Signed-off-by: Jo-Philipp Wich <jo@mein.io>