Investigate VS2015 test error

appveyor.yml

@@ -8,33 +8,6 @@ configuration: Release
 
 environment:
   matrix:
-    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
-      G: "Ninja"
-      BOOST_ROOT: C:\Libraries\boost_1_84_0
-      MSSQL_VER: 2019
-      POSTGRESQL_ROOT: C:\Program Files\PostgreSQL\15
-      POSTGRESQL_VER: 15
-      MYSQL_VER: 80
-      MYSQL_DIR: C:\Program Files\MySql\MySQL Server 8.0
-      VCVARS_SCRIPT: "C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Auxiliary/Build"
-    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      G: "Ninja"
-      BOOST_ROOT: C:\Libraries\boost_1_77_0
-      MSSQL_VER: 2017
-      POSTGRESQL_ROOT: C:\Program Files\PostgreSQL\13
-      POSTGRESQL_VER: 13
-      MYSQL_VER: 80
-      MYSQL_DIR: C:\Program Files\MySql\MySQL Server 8.0
-      VCVARS_SCRIPT: "C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/VC/Auxiliary/Build"
-    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
-      G: "Ninja"
-      BOOST_ROOT: C:\Libraries\boost_1_69_0
-      MSSQL_VER: 2016
-      POSTGRESQL_ROOT: C:\Program Files\PostgreSQL\12
-      POSTGRESQL_VER: 12
-      MYSQL_VER: 57
-      MYSQL_DIR: C:\Program Files\MySql\MySQL Server 5.7
-      VCVARS_SCRIPT: "C:/Program Files (x86)/Microsoft Visual Studio/2017/Community/VC/Auxiliary/Build"
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       G: "Ninja"
       BOOST_ROOT: C:\Libraries\boost_1_60_0
@@ -44,16 +17,6 @@ environment:
       MYSQL_VER: 57
       MYSQL_DIR: C:\Program Files\MySql\MySQL Server 5.7
       VCVARS_SCRIPT: "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC"
-    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-      G: "MinGW Makefiles"
-      MINGW_BIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64\bin
-      MSSQL_VER: 2014
-      BOOST_ROOT: C:\Libraries\boost_1_60_0
-      POSTGRESQL_ROOT: C:\Program Files\PostgreSQL\9.4
-      POSTGRESQL_VER: 9.4
-      MYSQL_VER: 57
-      MYSQL_DIR: C:\Program Files\MySql\MySQL Server 5.7
-      VCVARS_SCRIPT: "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC"
 
 install:
   # Start these ones here as we can't specify the service name dynamically above.