[Ruby] fix `number.method` highlighting

[zufuliu]

Currently, when number has no dot (integer or complex), method is colored as fractional part of float literal. Ruby-number-0114.patch

Removed numDots check, it's not required after check chNext, and trailing dot is used for method invoke.

test case:

# Float Literals
12.34
1234e-2
1.234E1
# Range Literals
(1..2)
(2.0..3)
# method
1.5.ceil
1ri.abs
3.times {|i| puts i}
3. times {|i| puts i}