patch 8.2.1074: Vim9: no line break allowed after some operators

Problem:    Vim9: no line break allowed after some operators.
Solution:   Skip a line break after the operator.  Add
            eval_may_get_next_line() to simplify checking for a line break.

src/testdir/test_vim9_expr.vim

@@ -64,6 +64,15 @@ def Test_expr1_vimscript()
       assert_equal('no', var)
   END
   CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+      let var = v:false ?
+      		'yes' :
+		'no'
+      assert_equal('no', var)
+  END
+  CheckScriptSuccess(lines)
 enddef
 
 func Test_expr1_fails()
@@ -135,6 +144,15 @@ def Test_expr2_vimscript()
       assert_equal(1, var)
   END
   CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+      let var = v:false ||
+      		v:true ||
+		v:false
+      assert_equal(1, var)
+  END
+  CheckScriptSuccess(lines)
 enddef
 
 func Test_expr2_fails()
@@ -198,6 +216,15 @@ def Test_expr3_vimscript()
       assert_equal(1, var)
   END
   CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+      let var = v:true &&
+      		v:true &&
+      		v:true
+      assert_equal(1, var)
+  END
+  CheckScriptSuccess(lines)
 enddef
 
 func Test_expr3_fails()
@@ -547,6 +574,14 @@ def Test_expr4_vimscript()
   END
   CheckScriptSuccess(lines)
 
+  lines =<< trim END
+      vim9script
+      let var = 123 ==
+      			123
+      assert_equal(1, var)
+  END
+  CheckScriptSuccess(lines)
+
   lines =<< trim END
       vim9script
       let list = [1, 2, 3]