chore: remove non-customized legacy owlbot.py scripts (#13771)

Remove legacy owlbot.py scripts that only use the default configuration.

This change introduces minor whitespace adjustments in README.md files
due to differences in template whitespace trimming between Go and
Jinja2. These differences do not affect the rendered documentation and
are a one-time migration cost.

For googleapis/librarian#6822

Author: yangyzs

java-accessapproval/README.md

@@ -147,8 +147,6 @@ the individual GitHub repository `github.com/GoogleAPIs/java-SERVICENAME`
 and on [google-cloud-java][g-c-j].
 
 ## Versioning
-
-
 This library follows [Semantic Versioning](http://semver.org/).
 
 

java-accessapproval/owlbot.py

@@ -147,8 +147,6 @@ the individual GitHub repository `github.com/GoogleAPIs/java-SERVICENAME`
 and on [google-cloud-java][g-c-j].
 
 ## Versioning
-
-
 This library follows [Semantic Versioning](http://semver.org/).
 
 

java-accesscontextmanager/README.md

@@ -14,7 +14,6 @@ Java idiomatic client for [Google Ad Manager API][product-docs].
 
 ## Quickstart
 
-
 If you are using Maven, add this to your pom.xml file:
 
 
@@ -127,8 +126,6 @@ the individual GitHub repository `github.com/GoogleAPIs/java-SERVICENAME`
 and on [google-cloud-java][g-c-j].
 
 ## Versioning
-
-
 This library follows [Semantic Versioning](http://semver.org/).
 
 

java-accesscontextmanager/owlbot.py

@@ -147,8 +147,6 @@ the individual GitHub repository `github.com/GoogleAPIs/java-SERVICENAME`
 and on [google-cloud-java][g-c-j].
 
 ## Versioning
-
-
 This library follows [Semantic Versioning](http://semver.org/).
 
 

java-admanager/README.md

@@ -152,8 +152,6 @@ the individual GitHub repository `github.com/GoogleAPIs/java-SERVICENAME`
 and on [google-cloud-java][g-c-j].
 
 ## Versioning
-
-
 This library follows [Semantic Versioning](http://semver.org/).