Polishing.

See #892

Author: mp911de

.github/dco.yml

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+require:
+  members: false

CONTRIBUTING.adoc

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 Spring Vault is released under the Apache 2.0 license. If you would like to contribute something or want to hack on the code this document should help you get started.
 
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 == Code of Conduct
 This project adheres to the Contributor Covenant link:CODE_OF_CONDUCT.adoc[code of conduct].
 By participating, you are expected to uphold this code. Please report unacceptable behavior to [email protected].
 
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 == Using GitHub Issues
 We use GitHub issues to track bugs and enhancements.
 If you have a general usage question please ask on https://stackoverflow.com[Stack Overflow].
@@ -18,21 +14,15 @@ The Spring Vault team and the broader community monitor the https://stackoverflo
 If you are reporting a bug, please help to speed up problem diagnosis by providing as much information as possible.
 Ideally, that would include a small sample project that reproduces the problem.
 
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 == Reporting Security Vulnerabilities
 If you think you have found a security vulnerability in Spring Vault please *DO NOT* disclose it publicly until we've had a chance to fix it.
 Please don't report security vulnerabilities using GitHub issues, instead head over to https://spring.io/security-policy and learn how to disclose them responsibly.
 
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 == Sign the Contributor License Agreement
 Before we accept a non-trivial patch or pull request we will need you to https://cla.pivotal.io/sign/spring[sign the Contributor License Agreement].
 Signing the contributor's agreement does not grant anyone commit rights to the main repository, but it does mean that we can accept your contributions, and you will get an author credit if we do.
 Active contributors might be asked to join the core team, and given the ability to merge pull requests.
 
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 == Code Conventions and Housekeeping
 None of these is essential for a pull request, but they will all help.  They can also be
 added after the original pull request but before a merge.
@@ -52,7 +42,5 @@ added after the original pull request but before a merge.
 * If no-one else is using your branch, please rebase it against the current main branch (or other target branch in the project).
 * When writing a commit message please follow https://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html[these conventions].
 
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 == Working with the Code
 For information on editing, building, and testing the code, see the https://github.com/spring-projects/spring-vault/wiki/Working-with-the-Code[Working with the Code] page on the project wiki.