Fix library exclusion bug in Sniffle image

sniffles/sniffles.def

@@ -14,6 +14,7 @@ From: default/alpine:3.14.0
   apk add --no-cache bash
 
   # Get Sniffles
+  cd /opt || exit 1
   git clone https://github.com/fritzsedlazeck/Sniffles.git
   cd Sniffles || exit 1
   git checkout $SNIFFLES_TAG
@@ -23,18 +24,17 @@ From: default/alpine:3.14.0
   cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr/local
   make
 
-  # Install Sniffles
-  cd ../bin/sniffles-core-$SNIFFLES_VERSION || exit 1
-  install -D -m 0755 sniffles -t /usr/local/bin
-  install -D -m 0755 sniffles-debug -t /usr/local/bin
-
-  # Cleanup repo
-  cd ../.. || exit 1
-  rm -rf Sniffles
+  # Add Sniffles to PATH
+  export PATH=/opt/Sniffles/bin/sniffles-core-$SNIFFLES_VERSION:$PATH
 
   # Cleanup packages
   apk del --no-cache .build-deps
 
+%environment
+  export SNIFFLES_VERSION='1.0.12'
+  export SNIFFLES_TAG="v${SNIFFLES_VERSION}b"
+  export PATH=/opt/Sniffles/bin/sniffles-core-$SNIFFLES_VERSION:$PATH
+
 %test
   command -v bash
   command -v ps
@@ -47,7 +47,7 @@ From: default/alpine:3.14.0
 %labels
   Author 25492070+MillironX@users.noreply.github.com
   SoftwareVersion v1.0.12b
-  SingularityDefinitionVersion 1
+  SingularityDefinitionVersion 2
 
 %help
   Sniffles