Fix docs for using YAML to configure Log4J 2

Previously, the documentation stated that jackson-dataformat-yaml was
the only required dependency. This is incorrect. jackson-databind is
also required.

Closes gh-4924

Author: wilkinsona

spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -1259,14 +1259,25 @@ samples for more detail and to see it in action.
 [[howto-configure-log4j-for-logging-yaml-or-json-config]]
 ==== Use YAML or JSON to configure Log4j 2
 In addition to its default XML configuration format, Log4j 2 also supports YAML and JSON
-configuration files. To configure Log4j 2 to use an alternative configuration file format
-all you need to do is add an appropriate dependency to the classpath. To use YAML, add a
-dependency on `com.fasterxml.jackson.dataformat:jackson-dataformat-yaml` and Log4j 2 will
-look for configuration files names `log4j2.yaml` or `log4j2.yml`. To use JSON, add a
-dependency on `com.fasterxml.jackson.core:jackson-databind` and Log4j 2 will look for
-configuration files named `log4j2.json` or `log4j2.jsn`
-
+configuration files. To configure Log4j 2 to use an alternative configuration file format,
+add the appropriate dependencies to the classpath and name your
+configuration files to match your chosen file format:
 
+[cols="10,75,15"]
+|===
+|Format|Dependencies|File names
+
+|YAML
+a| `com.fasterxml.jackson.core:jackson-databind` +
+   `com.fasterxml.jackson.dataformat:jackson-dataformat-yaml`
+a| `log4j2.yaml` +
+   `log4j2.yml`
+
+|JSON
+a| `com.fasterxml.jackson.core:jackson-databind`
+a| `log4j2.json` +
+   `log4j2.jsn`
+|===
 
 [[howto-data-access]]
 == Data Access