📖 Remove trailing whitespace (#2241)

Remove trailing whitespace in README.md and checks.yaml.

Trailing whitespace creates long-term hidden problems, because
in most editors they aren't visible, yet changing them creates
what appear to be spurious changes. They can also create
surprising merge conflicts. Removing them removes the problem
long term.

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

README.md

@@ -34,7 +34,7 @@
 -   [Default Scorecards Checks](#scorecard-checks)
 -   [Detailed Check Documentation](docs/checks.md) (Scoring Criteria, Risks, and
     Remediation)
-    
+
 ## Scoring
 -   [Aggregate Score](#aggregate-score)
 
@@ -55,8 +55,8 @@ ________________________________________________________________________________
 ## Overview
 
 ### What is Scorecards?
-We created Scorecards to help open source maintainers improve their security 
-best practices and to help open source consumers judge whether their dependencies 
+We created Scorecards to help open source maintainers improve their security
+best practices and to help open source consumers judge whether their dependencies
 are safe.
 
 Scorecards is an automated tool that assesses a number of important heuristics
@@ -142,15 +142,15 @@ Action
 
 ### Scorecards REST API
 
-To query pre-calculated scores of OSS projects, use the [REST API](https://api.securityscorecards.dev). 
+To query pre-calculated scores of OSS projects, use the [REST API](https://api.securityscorecards.dev).
 
-To enable your project to be available on the REST API, set 
-[`publish_results: true`](https://github.com/ossf/scorecard-action/blob/dd5015aaf9688596b0e6d11e7f24fff566aa366b/action.yaml#L35) 
+To enable your project to be available on the REST API, set
+[`publish_results: true`](https://github.com/ossf/scorecard-action/blob/dd5015aaf9688596b0e6d11e7f24fff566aa366b/action.yaml#L35)
 in the Scorecards GitHub Action setting.
 
 ### Scorecards Badges
 
-Enabling [`publish_results: true`](https://github.com/ossf/scorecard-action/blob/dd5015aaf9688596b0e6d11e7f24fff566aa366b/action.yaml#L35) 
+Enabling [`publish_results: true`](https://github.com/ossf/scorecard-action/blob/dd5015aaf9688596b0e6d11e7f24fff566aa366b/action.yaml#L35)
 in Scorecards GitHub Actions also allows maintainers to display a Scorecard badge on their repository to show off their
 hard work. This badge also auto-updates for every change made to the repository.
 To include a badge on your project's repository, simply add the following markdown to your README:
@@ -208,7 +208,7 @@ We generate [SLSA3 signatures](slsa.dev) using the OpenSSF's [slsa-framework/sls
 
 ```shell
 slsa-verifier -artifact-path <the-zip> -provenance attestation.intoto.jsonl -source github.com/ossf/scorecard -tag <the-tag>
-```  
+```
 
 ##### Using package managers