test: Use POSIX-compliant example for equals comparison (#11728)

* [: use posix-compliant example for equals comparison

the previous example worked fine for bash, but some
other shells (zsh, in my case) will not work when
using "==" for comparison. the posix spec only requires
"=", so I think it makes a little more sense to use
that in the example.

* test: use posix-compliant example for equals comparison

the previous example worked fine for bash, but some
other shells (zsh, in my case) will not work when
using "==" for comparison. the posix spec only requires
"=", so I think it makes a little more sense to use
that in the example.

pages.ja/common/[.md

@@ -6,7 +6,7 @@
 
 - 与えられた変数が与えられた文字列と等しいかどうかをテスト:
 
-`[ "{{$変数名}}" == "{{/bin/zsh}}" ]`
+`[ "{{$変数名}}" = "{{/bin/zsh}}" ]`
 
 - 与えられた変数が空であるかどうかをテスト:
 

pages.ja/common/test.md

@@ -6,7 +6,7 @@
 
 - 与えられた変数が与えられた文字列と等しいかどうかをテスト:
 
-`test "{{$変数名}}" == "{{/bin/zsh}}"`
+`test "{{$変数名}}" = "{{/bin/zsh}}"`
 
 - 与えられた変数が空であるかどうかをテスト: