[mod] drop SearXNG's checker (#5767)

To date, there is no analysis for the checker that could be evaluated in any
meaningful way.

- https://github.com/searxng/searxng/issues/3407
- https://github.com/searxng/searxng/pull/3312

The checker would need to be completely redesigned, but even then, its
usefulness and the maintenance required for it would be disproportionate.

TBH: In its current form, it is useless and only consumes resources and
causes the engines to be blocked, because these tests (query terms) come
from *hundreds* of instances and could be interpreted as bot attacks.

Related issues: [search.checker](https://github.com/searxng/searxng/issues?q=label%3A%22search.checker%22)

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

Makefile

@@ -17,7 +17,6 @@ help:
 	@echo 'install        - developer install of SearxNG into virtualenv'
 	@echo 'uninstall      - uninstall developer installation'
 	@echo 'clean          - clean up working tree'
-	@echo 'search.checker - check search engines'
 	@echo 'test           - run shell & CI tests'
 	@echo 'test.shell     - test shell scripts'
 	@echo 'ci.test        - run CI tests'
@@ -39,12 +38,6 @@ clean: py.clean docs.clean node.clean nvm.clean go.clean test.clean
 	$(Q)find . -name '*~' -exec rm -f {} +
 	$(Q)find . -name '*.bak' -exec rm -f {} +
 
-PHONY += search.checker search.checker.%
-search.checker: install
-	$(Q)./manage pyenv.cmd searxng-checker -v
-
-search.checker.%: install
-	$(Q)./manage pyenv.cmd searxng-checker -v "$(subst _, ,$(patsubst search.checker.%,%,$@))"
 
 PHONY += test ci.test test.shell
 test:    test.yamllint test.black test.pyright_modified test.pylint test.unit test.robot test.rst test.shell test.shfmt