KTL-2775 update env variables and remove trailing

Author: Quattro8

.teamcity/documentation/builds/KotlinMultiplatform.kt

@@ -40,11 +40,11 @@ object KotlinMultiplatform: BuildType ({
             scriptContent = """
                 docker run --rm -v %teamcity.build.checkoutDir%:/opt/sources \
                 -e SOURCE_DIR=/opt/sources \
-                -e PRODUCT=kotlin-multiplatform-docs/mpd \
+                -e MODULE_INSTANCE=kotlin-multiplatform-docs/mpd \
                 -e RUNNER=teamcity \
                 -e FRONTEND=https://kotlinlang.org/docs/static/v3/ \
                 -e OUTPUT_DIR=/opt/sources/artifacts \
-                registry.jetbrains.team/p/writerside/builder/writerside-builder:$dockerImageTag \
+                registry.jetbrains.team/p/writerside/builder/writerside-builder:$dockerImageTag
             """.trimIndent()
         }
     }