clang-tidy: Check for redundant expressions, unused "using"

Signed-off-by: Marcus Müller <[email protected]>

Author: marcusmueller

.clang-tidy

@@ -1,5 +1,5 @@
 ---
-Checks:          '-*,misc-throw-by-value-catch-by-reference,misc-static-assert,readability-container-size-empty,modernize-use-override,modernize-make-unique,modernize-deprecated-headers'
+Checks:          '-*,misc-throw-by-value-catch-by-reference,misc-static-assert,readability-container-size-empty,modernize-use-override,modernize-make-unique,modernize-deprecated-headers,misc-unused-using-decls,misc-redundant-expression'
 # Not in here: modernize-use-emplace, since that basically broke all things it touched
 WarningsAsErrors: ''
 HeaderFilterRegex: '\.(cc|c|cpp|h|hpp)$'