update PR tempalte, issue template, link to validator (#21232)

Author: wing328

.github/ISSUE_TEMPLATE/bug_report.md

@@ -10,7 +10,7 @@ assignees: ''
 #### Bug Report Checklist
 
 - [ ] Have you provided a full/minimal spec to reproduce the issue?
-- [ ] Have you validated the input using an OpenAPI validator ([example](https://apitools.dev/swagger-parser/online/))?
+- [ ] Have you validated the input using an OpenAPI validator?
 - [ ] Have you [tested with the latest master](https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-to-test-with-the-latest-master-of-openapi-generator) to confirm the issue still exists?
 - [ ] Have you searched for related issues/PRs?
 - [ ] What's the actual output vs expected output?

.github/PULL_REQUEST_TEMPLATE.md

@@ -11,7 +11,7 @@
   ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
   ./bin/utils/export_docs_generators.sh || exit
   ``` 
-  (For Windows users, please run the script in [Git BASH](https://gitforwindows.org/))
+  (For Windows users, please run the script in [WSL](https://learn.microsoft.com/en-us/windows/wsl/install))
   Commit all changed files. 
   This is important, as CI jobs will verify _all_ generator outputs of your HEAD commit as it would merge with master. 
   These must match the expectations made by your contribution. 

README.md

@@ -1023,7 +1023,7 @@ Here is a list of template creators:
    * Apex: @asnelling
    * Bash: @bkryza
    * C: @PowerOfCreation @zhemant [:heart:](https://www.patreon.com/zhemant)
-   * C++ REST: @Danielku15, @aminya
+   * C++ REST: @Danielku15
    * C++ Tiny: @AndersSpringborg @kaareHH @michelealbano @mkakbas
    * C++ UE4: @Kahncode
    * C# (.NET 2.0): @who