Fix test failures when language environment is not UTF-8.

For tests that depend on UTF-8 encoding, force LC_COLLATE=C and
LC_CTYPE=C to avoid an encoding mismatch.

Reported-by: Thomas Munro
Discussion: https://postgr.es/m/CA+hUKGK-ZqV1njkG_=xcCqXh2fcMkz85FTMnhS2opm4ZerH=xw@mail.gmail.com

Author: jeff-davis

src/bin/initdb/t/001_initdb.pl

@@ -200,6 +200,7 @@
 	[
 		'initdb', '--no-sync',
 		'--locale-provider=builtin', '-E UTF-8',
+		'--lc-collate=C', '--lc-ctype=C',
 		'--builtin-locale=C.UTF-8', "$tempdir/data8"
 	],
 	'locale provider builtin with -E UTF-8 --builtin-locale=C.UTF-8');
@@ -208,6 +209,7 @@
 	[
 		'initdb', '--no-sync',
 		'--locale-provider=builtin', '-E SQL_ASCII',
+		'--lc-collate=C', '--lc-ctype=C',
 		'--builtin-locale=C.UTF-8', "$tempdir/data9"
 	],
 	'locale provider builtin with --builtin-locale=C.UTF-8 fails for SQL_ASCII'

src/bin/scripts/t/020_createdb.pl

@@ -143,6 +143,7 @@
 	[
 		'createdb', '-T',
 		'template0', '--locale-provider=builtin',
+		'--lc-collate=C', '--lc-ctype=C',
 		'-E UTF-8', '--builtin-locale=C.UTF8',
 		'tbuiltin5'
 	],
@@ -152,6 +153,7 @@
 	[
 		'createdb', '-T',
 		'template0', '--locale-provider=builtin',
+		'--lc-collate=C', '--lc-ctype=C',
 		'-E LATIN1', '--builtin-locale=C.UTF-8',
 		'tbuiltin6'
 	],