Bump org.eclipse.jgit:org.eclipse.jgit in /opengrok-indexer

Bumps org.eclipse.jgit:org.eclipse.jgit from 5.12.0.202106070339-r to 6.6.1.202309021850-r.

---
updated-dependencies:
- dependency-name: org.eclipse.jgit:org.eclipse.jgit
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

opengrok-indexer/pom.xml

@@ -236,7 +236,7 @@ Portions Copyright (c) 2020-2020, Lubos Kosco <tarzanek@gmail.com>.
         <dependency>
             <groupId>org.eclipse.jgit</groupId>
             <artifactId>org.eclipse.jgit</artifactId>
-            <version>5.12.0.202106070339-r</version>
+            <version>6.6.1.202309021850-r</version>
         </dependency>
         <dependency>
             <groupId>io.github.g00fy2</groupId>