[Release] Update version to 8.19.7 (#3657)

Updates references to the new release 8.19.7.

Merge after the release 8.19.6.

Co-authored-by: elasticmachine <[email protected]>

Author: elastic-vault-github-plugin-prod[bot]

version/version.go

@@ -18,7 +18,7 @@
 package version
 
 // name matches github.com/elastic/beats/v7/dev-tools/mage/settings.go parseBeatVersion
-const defaultBeatVersion = "8.19.6"
+const defaultBeatVersion = "8.19.7"
 
 // Version represents version information for a package
 type Version struct {