Prefer gawk over awk if both are available.

libexec/pyenv-help

@@ -36,7 +36,7 @@ extract_initial_comment_block() {
 }
 
 collect_documentation() {
-  awk '
+  $(type -p gawk awk | head -1) '
     /^Summary:/ {
       summary = substr($0, 10)
       next

libexec/pyenv-version-file-read

@@ -9,7 +9,7 @@ if [ -e "$VERSION_FILE" ]; then
   # Read the first non-whitespace word from the specified version file.
   # Be careful not to load it whole in case there's something crazy in it.
   IFS="${IFS}"$'\r'
-  words=( $(cut -b 1-1024 "$VERSION_FILE" | awk '{ print($1) }') )
+  words=( $(cut -b 1-1024 "$VERSION_FILE" | $(type -p gawk awk | head -1) '{ print($1) }') )
   versions=("${words[@]}")
 
   if [ -n "$versions" ]; then