Adding support for log4shell (#37)

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- [x] I have read the
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      doc.
- [x] Tests for the changes have been added (for bug fixes / features).
- [x] Docs have been reviewed and added / updated if needed (for bug
fixes / features).

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- [ ] Bugfix
- [x] Feature
- [ ] Code style update (formatting, renaming)
- [ ] Refactoring (no functional changes, no api changes)
- [ ] Build related changes
- [ ] Documentation content changes
- [ ] Other (please describe):

## What is the current behavior

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link to a
relevant issue. -->

## What is the new behavior

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- Added support for testing for log4j
-
-

## Does this introduce a breaking change

- [ ] Yes
- [x] No

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---

Closes #{IssueNumber}

.pre-commit-hooks.yaml

@@ -21,3 +21,10 @@
   entry: hooks/snyk-test.sh
   language: script
   pass_filenames: false
+
+- id: snyk-log4shell
+  name: Snyk log4shell
+  description: Runs 'snyk log4shell' command
+  entry: hooks/snyk-log4shell.sh
+  language: script
+  pass_filenames: false

README.md

@@ -8,6 +8,7 @@
 1. [snyk-container](#snyk-container)
 2. [snyk-iac](#snyk-iac)
 3. [snyk-test](#snyk-test)
+4. [snyk-log4shell](#snyk-log4shell)
 
 ## Description
 
@@ -69,3 +70,13 @@ repos:
       - id: snyk-test
         args: ["--severity-threshold=critical"]
 ```
+
+### snyk-log4shell
+
+```yaml
+repos:
+  - repo: https://github.com/fabasoad/pre-commit-snyk
+    rev: <rev>
+    hooks:
+      - id: snyk-log4shell
+```

hooks/snyk-log4shell.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+set -eu
+SCRIPT_DIR="$(cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd)"
+bash "${SCRIPT_DIR}"/installation/main.sh
+
+snyk log4shell "$@"