Backport apm settings fixes 6.6 (#33343)

* fix spelling

# Conflicts:
#	docs/settings/apm-settings.asciidoc

* docs: add sentence on where to change apm settings (#27069)

* [DOCS] Removes X-Pack settings section (#30554)

Just the apm settings changes

* Updates * characters to an escaped * (#22269)

GitHub's asciidoc parser handles `*` characters fine but markdown thinks its italicizing unless you escape the first asterisk. Subsequent asterisks on the same line can stay unescaped and should work fine.

# Conflicts:
#	docs/settings/apm-settings.asciidoc

* fix conflicts

docs/settings/apm-settings.asciidoc

@@ -1,15 +1,17 @@
 [role="xpack"]
 [[apm-settings-kb]]
-=== APM Settings in Kibana
+=== APM settings in Kibana
 ++++
-<titleabbrev>APM Settings</titleabbrev>
+<titleabbrev>APM settings</titleabbrev>
 ++++
 
 You do not need to configure any settings to use APM. It is enabled by default.
+If you'd like to change any of the default values,
+copy and paste the relevant settings below into your `kibana.yml` configuration file.
 
 [float]
 [[general-apm-settings-kb]]
-==== General APM Settings
+==== General APM settings
 
 xpack.apm.enabled:: Set to `false` to disabled the APM plugin {kib}. Defaults to
 `true`.
@@ -19,7 +21,7 @@ xpack.apm.ui.enabled:: Set to `false` to hide the APM plugin {kib} from the menu
 
 xpack.apm.ui.transactionGroupBucketSize:: Number of top transaction groups displayed in APM plugin in Kibana. Defaults to `100`.
 
-apm_oss.indexPattern:: Index pattern is used for integrations with Machine Learning and Kuery Bar. It must match all apm indices. Defaults to `apm-&#42;`.
+apm_oss.indexPattern:: Index pattern is used for integrations with Machine Learning and Kuery Bar. It must match all apm indices. Defaults to `apm-*`.
 
 apm_oss.errorIndices:: Matcher for indices containing error documents. Defaults to `apm-*`.