Dead / wrong link to config file in Analyzer User guide

[johnfqg]

Describe the bug
In docs/analyzer/user_guide.md, section "Analysis configuration file", line 681, there's a link to Client Configuration file pointing to a non-existent file, docs/analyzer/config_file.md, I think this should point to docs/config_file.md instead.

CodeChecker version
6.25.1

To Reproduce
Analyzer user guide, section Analysis configuration file.

Expected behaviour
Reach the correct link.