[flang][docs] Remove passwords for bi-weekly flang calls from documen… (#98161)

…tation

The passwords are moved to the Google Doc containing the agenda and
minutes for the calls. A note has been added mentioning where to find
the meeting ID's and passwords.

Fixes #96121

Author: tarunprabhu

flang/docs/GettingInvolved.md

@@ -46,8 +46,8 @@ To understand the status of various developments in Flang please join the respec
 
 -   General updates on the Flang project.
 -   Join [Flang Community Biweekly Call](https://lanl-us.webex.com/lanl-us/j.php?MTID=mdce13c9bd55202e8071d8128fb953614)
-    - Meeting number: 177 400 7047
-    - Password: 6PCdCYKmN43
+    - If you prefer to join using a meeting number and password, those can be 
+      found in this [Google Doc](https://docs.google.com/document/d/1Z2U5UAtJ-Dag5wlMaLaW1KRmNgENNAYynJqLW2j2AZQ/). Alternative methods of joining, such as call-in numbers, are also available.
 -   Time: Wednesdays, 8:30 a.m. Pacific Time, on the weeks alternating with regular Flang Community Technical Biweekly Call.
 -   Meeting minutes are available in this [Google Doc](https://docs.google.com/document/d/1Z2U5UAtJ-Dag5wlMaLaW1KRmNgENNAYynJqLW2j2AZQ/edit).
 -   Minutes from older meetings were posted on the [Flang forum](https://discourse.llvm.org/c/subprojects/flang). Search for `Flang Biweekly Sync - Notes`.
@@ -56,8 +56,8 @@ To understand the status of various developments in Flang please join the respec
 
 -   Technical topics call.
 -   Join [Flang Community Technical Biweekly Call](https://teams.microsoft.com/l/meetup-join/19%3ameeting_YWU1NzU4ZjQtOTljOS00NWU1LTg5NjktYTUzOTU3MGEwMzAx%40thread.v2/0?context=%7b%22Tid%22%3a%22f34e5979-57d9-4aaa-ad4d-b122a662184d%22%2c%22Oid%22%3a%223641875c-ef5b-4767-8105-0787a195852f%22%7d)
-    - Meeting ID: 330 223 778 657
-    - Passcode: 7GjaJ3
+    - If you prefer to join using a meeting ID and passcode, those can be 
+      found in this [Google Doc](https://docs.google.com/document/d/1Z2U5UAtJ-Dag5wlMaLaW1KRmNgENNAYynJqLW2j2AZQ/). Alternative methods of joining, such as call-in numbers, are also available.
 -   Time: Mondays, 8:30 a.m. Pacific Time, on the weeks alternating with regular Flang Community Biweekly Call.
 -   The agenda is in this [Google Doc](https://docs.google.com/document/d/1Z2U5UAtJ-Dag5wlMaLaW1KRmNgENNAYynJqLW2j2AZQ/).