build(deps): bump github.com/containers/storage from 1.15.5 to 1.15.7

Bumps [github.com/containers/storage](https://github.com/containers/storage) from 1.15.5 to 1.15.7.
- [Release notes](https://github.com/containers/storage/releases)
- [Changelog](https://github.com/containers/storage/blob/master/docs/containers-storage-changes.md)
- [Commits](https://github.com/containers/storage/compare/v1.15.5...v1.15.7)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>
Signed-off-by: Matthew Heon <mheon@redhat.com>

vendor/github.com/mattn/go-shellwords/.travis.yml

@@ -11,4 +11,3 @@ script:
 
 after_success:
   - bash <(curl -s https://codecov.io/bash)
-

vendor/github.com/mattn/go-shellwords/README.md

@@ -2,6 +2,7 @@
 
 [![codecov](https://codecov.io/gh/mattn/go-shellwords/branch/master/graph/badge.svg)](https://codecov.io/gh/mattn/go-shellwords)
 [![Build Status](https://travis-ci.org/mattn/go-shellwords.svg?branch=master)](https://travis-ci.org/mattn/go-shellwords)
+[![GoDoc](https://godoc.org/github.com/mattn/go-shellwords?status.svg)](http://godoc.org/github.com/mattn/go-shellwords)
 
 Parse line as shell words.
 

vendor/github.com/mattn/go-shellwords/shellwords.go

@@ -144,11 +144,17 @@ loop:
 			}
 		case '"':
 			if !singleQuoted && !dollarQuote {
+				if doubleQuoted && buf == "" {
+					got = true
+				}
 				doubleQuoted = !doubleQuoted
 				continue
 			}
 		case '\'':
 			if !doubleQuoted && !dollarQuote {
+				if singleQuoted && buf == "" {
+					got = true
+				}
 				singleQuoted = !singleQuoted
 				continue
 			}