Rollup merge of #135679 - onur-ozkan:bootstrap-issue-template, r=jieyouxu

create an issue template for bootstrap

Resolves #135593

cc `@rust-lang/bootstrap`

Author: GuillaumeGomez

.github/ISSUE_TEMPLATE/bootstrap.md

@@ -0,0 +1,70 @@
+---
+name: Bootstrap (Rust Build System) Report
+about: Issues encountered on bootstrap build system
+labels: C-bug, T-bootstrap
+---
+
+<!--
+Thank you for submitting a bootstrap report! Please provide detailed information to help us reproduce and diagnose the issue.
+-->
+
+### Summary
+
+<!--
+Provide a brief description of the problem you are experiencing.
+-->
+
+### Command used
+
+```sh
+<command>
+```
+
+### Expected behaviour
+
+<!--
+Describe what you expected to happen.
+-->
+
+### Actual behaviour
+
+<!--
+Describe what actually happened.
+-->
+
+### Bootstrap configuration (config.toml)
+```toml
+<config>
+```
+
+### Operating system
+
+<!--
+e.g., Ubuntu 22.04, macOS 12, Windows 10
+-->
+
+### HEAD
+
+<!--
+Output of `git rev-parse HEAD` command, or content of the `git-commit-hash` file if using a tarball source.
+-->
+
+### Additional context
+<!--
+Include any other relevant information (e.g., if you have custom patches or modifications on the project).
+-->
+
+
+<!--
+Include the complete build log in the section below.
+Enable backtrace and verbose mode if possible for more detailed information e.g., with `RUST_BACKTRACE=1 ./x build -v`.
+-->
+<details><summary>Build Log</summary>
+<p>
+
+```txt
+<log>
+```
+
+</p>
+</details>