Fix periodic boundary bug in AMReX-Codes#3199 (AMReX-Codes#3243)

PR AMReX-Codes#3199 broke the Nyx regression tests. The issue is we require the
particle positions to be in [plo, phi). This won't happen if rhi is
exactly equal to phi. The fix is to make sure rhi is always slightly
inside the domain.

EDIT - fixed this in a different way. Now, when applying periodic
boundaries, the particle positions will be set to be strictly less than
rhi.

Src/Particle/AMReX_ParticleUtil.H

@@ -569,8 +569,8 @@ bool enforcePeriodic (P& p,
     for (int idim = 0; idim < AMREX_SPACEDIM; ++idim)
     {
         if (! is_per[idim]) continue;
-        if (p.pos(idim) >= phi[idim]) {
-            while (p.pos(idim) >= phi[idim]) {
+        if (p.pos(idim) >= rhi[idim]) {
+            while (p.pos(idim) >= rhi[idim]) {
                 p.pos(idim) -= static_cast<ParticleReal>(phi[idim] - plo[idim]);
             }
             // clamp to avoid precision issues;
@@ -579,13 +579,13 @@ bool enforcePeriodic (P& p,
             }
             shifted = true;
         }
-        else if (p.pos(idim) < plo[idim]) {
-            while (p.pos(idim) < plo[idim]) {
+        else if (p.pos(idim) < rlo[idim]) {
+            while (p.pos(idim) < rlo[idim]) {
                 p.pos(idim) += static_cast<ParticleReal>(phi[idim] - plo[idim]);
             }
             // clamp to avoid precision issues;
-            if (p.pos(idim) > rhi[idim]) {
-                p.pos(idim) = rhi[idim];
+            if (p.pos(idim) >= rhi[idim]) {
+                p.pos(idim) = std::nextafter(p.pos(idim), rlo[idim]);
             }
             shifted = true;
         }