* fix broken link in 09-backups.md (#2761)

* fix broken link embedded in `systemd` status command output `041-database-mariadb.md`

Author: sspencerwire

docs/books/admin_guide/09-backups.md

@@ -543,7 +543,7 @@ keys:
     **wildcard (wildcard character)**: used to match file or directory names. 
     **regular expression**: used to match the content of a file.
 
-    You can see an introduction with extra detail in [this document](../sed_awk_grep/1_regular _expressions_vs_wildcards.md).
+    You can see an introduction with extra detail in [this document](../sed_awk_grep/1_regular_expressions_vs_wildcards.md). 
 
 ## *CoPy Input Output* - `cpio`
 

docs/books/web_services/041-database-servers-mariadb.md

@@ -416,7 +416,7 @@ $ sudo systemctl status mariadb
      Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; preset: disabled)
      Active: active (running) since Thu 2024-06-20 11:48:56 CEST; 1min 27s ago
        Docs: man:mariadbd(8)
-             https://mariadb.com/kb/en/library/systemd/
+             https://mariadb.com
     Process: 6538 ExecStartPre=/usr/libexec/mariadb-check-socket (code=exited, status=0/SUCCESS)
     Process: 6560 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir mariadb.service (code=exited, status=0/SUCCESS)
     Process: 6658 ExecStartPost=/usr/libexec/mariadb-check-upgrade (code=exited, status=0/SUCCESS)