chore(deps): Bump fastmcp

Bumps the minor-and-patch group in /mcp/slack_tool with 1 update: [fastmcp](https://github.com/PrefectHQ/fastmcp).


Updates `fastmcp` from 3.4.2 to 3.4.4
- [Release notes](https://github.com/PrefectHQ/fastmcp/releases)
- [Changelog](https://github.com/PrefectHQ/fastmcp/blob/main/docs/changelog.mdx)
- [Commits](PrefectHQ/fastmcp@v3.4.2...v3.4.4)

---
updated-dependencies:
- dependency-name: fastmcp
  dependency-version: 3.4.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: minor-and-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

mcp/slack_tool/pyproject.toml

@@ -10,7 +10,7 @@ dependencies = [
     "authlib>=1.7.2",   # Indirect; prevents CVE-2026-27962
     "urllib3>=2.7.0",   # Indirect; prevents CVE-2025-66418
     "python-multipart>=0.0.32", # Indirect; prevents CVE-2026-24486
-    "fastmcp>=3.4.2",           # Indirect; prevents CVE-2026-32871
+    "fastmcp>=3.4.4",           # Indirect; prevents CVE-2026-32871
     "starlette>=1.3.1",        # Indirect; prevents CVE-2025-62727
     "cryptography>=48.0.0,<49", # Indirect; prevents CVE-2026-26007
 ]