Polish documentation headings

Title case should be used in all headings.

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/actuator/metrics.adoc

@@ -28,7 +28,7 @@ TIP: To learn more about Micrometer's capabilities, see its {url-micrometer-docs
 
 
 [[actuator.metrics.getting-started]]
-== Getting started
+== Getting Started
 
 Spring Boot auto-configures a composite `MeterRegistry` and adds a registry to the composite for each of the supported implementations that it finds on the classpath.
 Having a dependency on `micrometer-registry-\{system}` in your runtime classpath is enough for Spring Boot to configure the registry.
@@ -206,7 +206,7 @@ This is the default behavior and requires no special setup beyond a dependency o
 
 
 [[actuator.metrics.export.dynatrace.v2-api.manual-config]]
-===== Manual configuration
+===== Manual Configuration
 
 If no auto-configuration is available, the endpoint of the {url-dynatrace-docs-shortlink}/api-metrics-v2-post-datapoints[Metrics v2 API] and an API token are required.
 The {url-dynatrace-docs-shortlink}/api-authentication[API token] must have the "`Ingest metrics`" (`metrics.ingest`) permission set.

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/actuator/observability.adoc

@@ -30,7 +30,7 @@ To enable it, add the `io.r2dbc:r2dbc-proxy` dependency to your project.
 
 
 [[actuator.observability.common-tags]]
-== Common tags
+== Common Tags
 
 Common tags are generally used for dimensional drill-down on the operating environment, such as host, instance, region, stack, and others.
 Common tags are applied to all observations as low cardinality tags and can be configured, as the following example shows:

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/features/dev-services.adoc

@@ -1,5 +1,5 @@
 [[features.dev-services]]
-= Development-time services
+= Development-time Services
 
 Development-time services provide external dependencies needed to run the application while developing it.
 They are only supposed to be used while developing and are disabled when the application is deployed.

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/features/kotlin.adoc

@@ -98,7 +98,7 @@ Among other things, the extensions make it possible to take advantage of Kotlin
 
 
 [[features.kotlin.dependency-management]]
-== Dependency management
+== Dependency Management
 
 In order to avoid mixing different versions of Kotlin dependencies on the classpath, Spring Boot imports the Kotlin BOM.
 
@@ -155,7 +155,7 @@ If you need the `MockK` equivalent of the Mockito specific xref:testing/spring-b
 
 
 [[features.kotlin.resources.further-reading]]
-=== Further reading
+=== Further Reading
 
 * {url-kotlin-docs}[Kotlin language reference]
 * https://kotlinlang.slack.com/[Kotlin Slack] (with a dedicated #spring channel)

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/messaging/rsocket.adoc

@@ -28,7 +28,7 @@ Note that their `@Order` is important, as it determines the order of codecs.
 
 
 [[messaging.rsocket.server-auto-configuration]]
-== RSocket server Auto-configuration
+== RSocket Server Auto-configuration
 
 Spring Boot provides RSocket server auto-configuration.
 The required dependencies are provided by the `spring-boot-starter-rsocket`.
@@ -63,7 +63,7 @@ spring:
 
 
 [[messaging.rsocket.messaging]]
-== Spring Messaging RSocket support
+== Spring Messaging RSocket Support
 
 Spring Boot will auto-configure the Spring Messaging infrastructure for RSocket.
 

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/packaging/aot.adoc

@@ -1,5 +1,5 @@
 [[packaging.aot]]
-= Ahead-of-time Processing With the JVM
+= Ahead-of-Time Processing With the JVM
 
 It's beneficial for the startup time to run your application using the AOT generated initialization code.
 First, you need to ensure that the jar you are building includes AOT generated code.

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/packaging/native-image/advanced-topics.adoc

@@ -171,7 +171,7 @@ But when you work with `WebClient`, `RestClient` or `RestTemplate` directly, you
 
 
 [[packaging.native-image.advanced.custom-hints.testing]]
-=== Testing custom hints
+=== Testing Custom Hints
 
 The `RuntimeHintsPredicates` API can be used to test your hints.
 The API provides methods that build a `Predicate` that can be used to test a `RuntimeHints` instance.

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/web/spring-graphql.adoc

@@ -153,7 +153,7 @@ Spring Boot will automatically detect `DataFetcherExceptionResolver` beans and r
 
 
 [[web.graphql.graphiql]]
-== GraphiQL and Schema printer
+== GraphiQL and Schema Printer
 
 Spring GraphQL offers infrastructure for helping developers when consuming or developing a GraphQL API.