fix: correct typos in E-Mail Settings and Organizations sections .env.example (#17258)

- Corrected "Sengrid" to "Sendgrid" in E-Mail Settings.
- Fixed "sing-ups" to "sign-ups" in the Organizations section.
- Corrected "envrionment" to "environment" in LICENSE (DEPRECATED).

.env.example

@@ -16,7 +16,7 @@
 # - Acquire a commercial license to remove these terms by visiting: cal.com/sales
 #
 
-# To enable enterprise-only features please add your envrionment variable to the .env file then make your way to /auth/setup to select your license and follow instructions. 
+# To enable enterprise-only features please add your environment variable to the .env file then make your way to /auth/setup to select your license and follow instructions. 
 CALCOM_LICENSE_KEY=
 # Signature token for the Cal.com License API (used for self-hosted integrations)
 # We will give you a token when we provide you with a license key this ensure you and only you can communicate with the Cal.com License API for your license key
@@ -128,7 +128,7 @@ GOOGLE_API_CREDENTIALS=
 # Inbox to send user feedback
 SEND_FEEDBACK_EMAIL=
 
-# Sengrid
+# Sendgrid
 # Used for email reminders in workflows and internal sync services
 SENDGRID_API_KEY=
 SENDGRID_EMAIL=
@@ -262,7 +262,7 @@ ORGANIZATIONS_ENABLED=
 NEXT_PUBLIC_ORGANIZATIONS_MIN_SELF_SERVE_SEATS=30
 NEXT_PUBLIC_ORGANIZATIONS_SELF_SERVE_PRICE=3700 # $37.00 per seat
 
-# This variable should only be set to 1 or true if you want to autolink external provider sing-ups with
+# This variable should only be set to 1 or true if you want to autolink external provider sign-ups with
 # existing organizations based on email domain address
 ORGANIZATIONS_AUTOLINK=