Cannot compile Redis 6.2.6 when tests passed

Question

I could not install redis-cli version 6 with apt install redis-tools, only version 5.0.7 was installed:

$ redis-cli -v                                                                                          
redis-cli 5.0.7

So I decide compile it from source code using redis documentation. After missing libs (tcl and pkg-config) I still cannot compile it. My tests pass without any problem:

$ make test
...
...
...
\o/ All tests passed without errors!

It looks like it should be OK, but make command cannot compile it and ask me to run tests again:

$ make                                                                                                         
cd src && make all
make[1]: Entering directory '/home/dorinand/Downloads/redis-6.2.6/src'

Hint: It's a good idea to run 'make test' ;)

make[1]: Leaving directory '/home/dorinand/Downloads/redis-6.2.6/src'

Can anybody help me to compile it and explain, why tests passed even it cannot be compiled?

I am using Ubuntu 20.04.3 LTS.