Fix two broken CONTRIBUTING.md links in the pre-work issue template

### Overview

We need to correct two links in the pre-work issue template that point to the wrong place in `CONTRIBUTING.md`, so new members aren't sent to a dead or incorrect section on their first day. One anchor doesn't exist at all, and the other silently scrolls to the wrong section.

### Action Items

- [ ] In `.github/ISSUE_TEMPLATE/pre-work-template-devops-security.md` line 29, change the "Login as root user & setup MFA" link anchor from `#login-as-root-user-&-setup-mfa` to `#login-as-root-user--setup-mfa`. GitHub strips `&` when generating heading anchors, which leaves two hyphens.
- [ ] On line 31, change the "Creating an IAM User" link anchor from `#create-an-iam-group` to `#create-an-iam-user`. Line 32 ("Creating an IAM Group") already points at `#create-an-iam-group` correctly and should be left alone.
- [ ] Open the rendered `CONTRIBUTING.md` and confirm both links now scroll to their matching sections.

### Resources/Instructions

- File to change: [pre-work-template-devops-security.md](https://github.com/hackforla/devops-security/blob/main/.github/ISSUE_TEMPLATE/pre-work-template-devops-security.md) (lines 29 and 31)
- Target document: [CONTRIBUTING.md](https://github.com/hackforla/devops-security/blob/main/CONTRIBUTING.md)
- **Line numbers were accurate when this issue was written and may drift as the file is edited.** If they no longer match, find the links by their link text ("Login as root user & setup MFA" and "Creating an IAM User") rather than by line number.
- The anchors are valid; only these two links are wrong. The other four `CONTRIBUTING.md` links in the template were checked and are correct.
- Both target headings are written as list items (`- ### **Create an IAM User**`). GitHub still generates anchors for these, so no change to `CONTRIBUTING.md` is needed.
- [GitHub docs: section links and heading anchors](https://docs.github.com/en/get-started/writing-on-github/getting-started-with-writing-and-formatting-on-github/basic-writing-and-formatting-syntax#section-links)
- Note: pre-work issues already opened keep the old links; only newly created ones pick up the fix.

打开 .github/ISSUE_TEMPLATE/pre-work-template-devops-security.md；如果列出的行发生了偏移，请根据链接文本定位这些链接。将这两个锚点与渲染后的 CONTRIBUTING.md 中对应的标题进行比较，只更新这些链接，并确认现在两者都会滚动到正确的部分；保持 IAM Group 链接不变。

由索引模型根据 Issue 内容生成。