Fix clang-tidy modernize-use-override findings

.clang-tidy

@@ -12,6 +12,7 @@ Checks: [-*,
          modernize-use-default-member-init,
          modernize-use-emplace,
          modernize-use-nullptr,
+         modernize-use-override,
 
          # Enable a very limited number of the cppcoreguidelines checkers.
          # See the notes for some of the rest of them below.

src/logging/Manager.cc

@@ -64,7 +64,7 @@ using DelayInfoPtr = std::shared_ptr<DelayInfo>;
 class LogDelayTokenVal : public OpaqueVal {
 public:
     explicit LogDelayTokenVal(DelayTokenType token) : OpaqueVal(zeek::detail::log_delay_token_type), token(token) {}
-    virtual ~LogDelayTokenVal() = default;
+    ~LogDelayTokenVal() override {};
 
     ValPtr DoClone(CloneState* state) override;