refactor: improve code quality and efficiency in various files (#548)

- Replace loadConfig() with _ = loadConfig()
- Update file permissions from 0660 to 0o660
- Simplify variable declarations
- Replace golang.org/x/crypto/ssh/terminal with golang.org/x/term
- Remove unused getCertPrincipals function
- Replace time.Now().Sub() with time.Since()
- Add test for ArgToIndex function

Signed-off-by: appleboy <appleboy.tw@gmail.com>

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-on: https://gitea.com/gitea/tea/pulls/548
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: techknowlogick <techknowlogick@noreply.gitea.io>
Co-authored-by: appleboy <appleboy.tw@gmail.com>
Co-committed-by: appleboy <appleboy.tw@gmail.com>

modules/print/organization.go

@@ -12,7 +12,7 @@ import (
 
 // OrganizationDetails prints details of an org with formatting
 func OrganizationDetails(org *gitea.Organization) {
-	outputMarkdown(fmt.Sprintf(
+	_ = outputMarkdown(fmt.Sprintf(
 		"# %s\n%s\n\n- Visibility: %s\n- Location: %s\n- Website: %s\n",
 		org.UserName,
 		org.Description,