[LyX/master] Amend 1dc66608

[Scott Kostyshak]

commit 7368e5be2be2c24f5cb363443d86c72973bd2719
Author: Scott Kostyshak <skostysh at lyx.org>
Date:   Mon Apr 10 13:10:11 2023 -0400

    Amend 1dc66608
    
    Declare override, otherwise we get the following warning:
    
    src/insets/InsetListings.h:42:7: error: 'isEnvironment' overrides a member function but is not marked 'override' [-Werror,-Winconsistent-missing-override]
            bool isEnvironment() const { return !params().isInline(); }
                 ^
    src/insets/Inset.h:606:15: note: overridden virtual function is here
            virtual bool isEnvironment() const { return getLayout().latextype() == InsetLaTeXType::ENVIRONMENT; }
                         ^
    1 error generated.
---
 src/insets/InsetListings.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/insets/InsetListings.h b/src/insets/InsetListings.h
index 080b7b7..d75f968 100644
--- a/src/insets/InsetListings.h
+++ b/src/insets/InsetListings.h
@@ -39,7 +39,7 @@ public:
 	///
 	static std::string params2string(InsetListingsParams const &);
 	///
-	bool isEnvironment() const { return !params().isInline(); }
+	bool isEnvironment() const override { return !params().isInline(); }
 private:
 	///
 	bool isLabeled() const override { return true; }