Update Help Modal description following SAM RNG removal in #2665 (#2692)

## Description:

Updates the help modal text to reflect the removal of SAM RNG in #2665.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

Aotumuri

Co-authored-by: iamlewis <lewismmmm@gmail.com>

resources/lang/en.json

@@ -115,7 +115,7 @@
     "build_silo": "Missile Silo",
     "build_silo_desc": "Allows launching missiles.",
     "build_sam": "SAM Launcher",
-    "build_sam_desc": "Can intercept enemy missiles in its 100 pixel range. With a 100% hit chance for Atom Bomb, 80% for Hydrogen Bomb and 50% for individual MIRV Warheads. The SAM has a 7.5 second cooldown.",
+    "build_sam_desc": "Can intercept enemy missiles in its 100 pixel range. The SAM has a 7.5 second cooldown.",
     "build_atom": "Atom Bomb",
     "build_atom_desc": "Small explosive bomb that destroys territory, buildings, ships and boats. Spawns from the nearest Missile Silo and lands in the area you first clicked to build it.",
     "build_hydrogen": "Hydrogen Bomb",