Fix redis-cli test issues on tcl8.5. (#10386)
Fix redis-cli test issues on tcl8.5. (#10386)

Apparently using `\x` produces different results between tclsh 8.5 and
8.6, whereas `\u` is more consistent.
oranagra/redis,ofirluzon/redis,PKRoma/redis,oranagra/redis,antirez/redis,charsyam/redis,yossigo/redis,ofirluzon/redis,PKRoma/redis,neomantra/redis,soloestoy/redis,charsyam/redis,neomantra/redis,PKRoma/redis,charsyam/redis,antirez/redis,oranagra/redis,antirez/redis,oranagra/redis,neomantra/redis,soloestoy/redis,oranagra/redis,ofirluzon/redis,neomantra/redis,yossigo/redis,yossigo/redis,yossigo/redis,charsyam/redis,PKRoma/redis,soloestoy/redis,yossigo/redis,charsyam/redis,neomantra/redis,PKRoma/redis,soloestoy/redis,antirez/redis,soloestoy/redis,ofirluzon/redis,ofirluzon/redis