Handle missing ${name} in .tool-versions (fallback to "lastest")

With set -euo pipefail, this grep | ... | grep pipeline will terminate the
script when there is no matching docker/${name} entry in .tool-versions (a
normal case). The command substitution should tolerate no matches and fall back
to latest.

Author: cgitim

scripts/docker/docker.lib.sh

@@ -188,7 +188,7 @@ function docker-get-image-version-and-pull() {
   local versions_file="${TOOL_VERSIONS:=$(git rev-parse --show-toplevel)/.tool-versions}"
   local version="latest"
   if [[ -f "$versions_file"  ]]; then
-    line=$(grep "docker/${name} " "$versions_file" | sed "s/^#\s*//; s/\s*#.*$//" | grep "${match_version:-".*"}")
+    line=$(grep "docker/${name} " "$versions_file" | sed "s/^#\s*//; s/\s*#.*$//" | grep "${match_version:-".*"}" || true)
     [ -n "$line" ] && version=$(echo "$line" | awk '{print $2}')
   fi