Work around bug in crash.shell pom that causes crash.cli to go AWOL

When spring-boot-docs is built on Windows, Maven logs a warning:

[WARNING] The POM for org.crashub:crash.shell:jar:1.3.2 is invalid,
transitive dependencies (if any) will not be available, enable debug
logging for more details

The build then fails as a class in crash.cli, a dependency of
crash.shell, is unavailable. The failure’s due to a hardcoded path
in the pom that Maven needs to be absolute and isn’t on Windows. See
https://jira.exoplatform.org/browse/CRASH-247 for details.

This commit works around the problem by explicitly declaring
crash.shell’s one dependency directly. The warning is still logged but
it’s now benign.

Closes gh-5633

spring-boot-docs/pom.xml

@@ -292,6 +292,11 @@
 			<artifactId>groovy-templates</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.crashub</groupId>
+			<artifactId>crash.cli</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.crashub</groupId>
 			<artifactId>crash.shell</artifactId>