Appveyor: always log the compiler path and version

Implements 27449.

.appveyor.yml

@@ -39,6 +39,8 @@ build_script:
             Execute-Bash 'autoreconf -i'
             mkdir "${env:build}"
             Set-Location "${env:build}"
+            Execute-Bash "which ${env:target}-gcc"
+            Execute-Bash "${env:target}-gcc --version"
             Execute-Bash "../configure --prefix=/${env:compiler_path} --build=${env:target} --host=${env:target} --disable-asciidoc --enable-fatal-warnings --with-openssl-dir=${env:openssl_path}"
             Execute-Bash "V=1 make -j2"
             Execute-Bash "V=1 make -j2 install"

changes/ticket27449

@@ -0,0 +1,3 @@
+  o Minor features (continuous integration):
+    - Log the compiler path and version during Appveyor builds.
+      Implements ticket 27449.